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17 <title>The Fetchmail FAQ</title>
18 <meta name="description"
19 content="Frequently asked questions about fetchmail."/>
20 <meta name="keywords" content="fetchmail, POP, POP2, POP3, IMAP, remote mail"/>
23 <table width="100%" cellpadding="0" summary="Canned page footer">
25 <td width="30%">Back to <a href="index.html">Fetchmail Home
27 <td width="30%" align="right">$Date$</td>
32 <h1 id="FAQ">Frequently Asked Questions About Fetchmail</h1>
34 <p><strong>Support? Bug reports?</strong> Please read <a
35 href="#G3">G3</a> for what information is required to get your problem
36 solved as quickly as possible.</p>
38 <p>Note that this FAQ is occasionally updated from the SVN repository
39 and speaks in the past tense ("since") about a fetchmail release that is
40 not yet available. Please try a release candidate for that version in
41 case you need the new option.</p>
43 <p>If you have a question or answer you think ought to be added to
44 this FAQ list, file it to one of the trackers at <a
45 href="http://developer.berlios.de/projects/fetchmail/">our BerliOS
46 project site</a> or post to one of the fetchmail mailing lists (see
49 <h1 id="Contents">Contents</h1>
51 <a href="#Contentdetail">Detailed Contents</a><br/>
52 <a href="#C_G">G. General problems</a><br/>
53 <a href="#C_B">B. Build-time problems</a><br/>
54 <a href="#C_F">F. Fetchmail configuration file grammar questions</a><br/>
55 <a href="#C_C">C. Configuration questions</a><br/>
56 <a href="#C_T">T. How to make fetchmail play nice with various MTAs</a><br/>
57 <a href="#C_S">S. How to make fetchmail work with various servers</a><br/>
58 <a href="#C_I">I. How to fetchmail work with specific ISPs</a><br/>
59 <a href="#C_K">K. How to set up well-known security and authentication</a><br/>
60 <a href="#C_R">R. Runtime fatal errors</a><br/>
61 <a href="#C_H">H. Hangs and lockups</a><br/>
62 <a href="#C_D">D. Disappearing mail</a><br/>
63 <a href="#C_M">M. Multidrop-mode problems</a><br/>
64 <a href="#C_X">X. Mangled mail</a><br/>
65 <a href="#C_O">O. Other problems</a><br/>
67 <h1 id="Contentdetail">Detailed Contents</h1>
69 <h2 id="C_G">General problems</h2>
71 <a href="#G1">G1. What is fetchmail and why should I bother?</a><br/>
72 <a href="#G2">G2. Where do I find the latest FAQ and fetchmail sources?</a><br/>
73 <a href="#G3">G3. Something doesn't work/I think I've found a bug. Will you fix it?</a><br/>
74 <a href="#G4">G4. I have this idea for a neat feature. Will you add it?</a><br/>
75 <a href="#G5">G5. I want to make fetchmail remove kept mail after some days.</a><br/>
76 <a href="#G6">G6. Is there a mailing list for exchanging tips?</a><br/>
77 <a href="#G7">G7. So, what's this I hear about a fetchmail paper?</a><br/>
78 <a href="#G8">G8. What is the best server to use with fetchmail?</a><br/>
79 <a href="#G9">G9. What is the best mail program to use with fetchmail?</a><br/>
80 <a href="#G10">G10. How can I avoid sending my password en clair?</a><br/>
81 <a href="#G11">G11. Is any special configuration needed to use a dynamic IP address?</a><br/>
82 <a href="#G12">G12. Is any special configuration needed to use firewalls?</a><br/>
83 <a href="#G13">G13. Is any special configuration needed to <em>send</em> mail?</a><br/>
84 <a href="#G14">G14. Is fetchmail Y2K-compliant?</a><br/>
85 <a href="#G15">G15. Is there a way in fetchmail to support disconnected IMAP mode?</a><br/>
86 <a href="#G16">G16. How will fetchmail perform under heavy loads?</a><br/>
89 <h2 id="C_B">Build-time problems</h2>
91 <a href="#B1"><strike>B1. Make coughs and dies when building on FreeBSD.</strike></a><br/>
92 <a href="#B2">B2. Lex bombs out while building the fetchmail lexer.</a><br/>
93 <a href="#B3">B3. I get link failures when I try to build fetchmail.</a><br/>
94 <a href="#B4">B4. I get build failures in the intl directory.</a><br/>
96 <h2 id="C_F">Fetchmail configuration file grammar questions</h2>
98 <a href="#F1">F1. Why does my old .fetchmailrc no longer work?</a><br/>
99 <a href="#F2">F2. The .fetchmailrc parser won't accept my all-numeric user name.</a><br/>
100 <a href="#F3">F3. The .fetchmailrc parser won't accept my host or username beginning with 'no'.</a><br/>
101 <a href="#F4">F4. I'm getting a 'parse error' message I don't understand.</a><br/>
103 <h2 id="C_C">Configuration questions</h2>
105 <a href="#C1">C1. Why do I need a .fetchmailrc when running as root
106 on my own machine?</a><br/>
107 <a href="#C2">C2. How can I arrange for a fetchmail daemon to get
108 killed when I log out?</a><br/>
109 <a href="#C3">C3. How do I know what interface and address to use
110 with --interface?</a><br/>
111 <a href="#C4">C4. How can I set up support for sendmail's anti-spam
113 <a href="#C5">C5. How can I poll some of my mailboxes more/less
114 often than others?</a><br/>
115 <a href="#C6">C6. Fetchmail works OK started up manually, but not
116 from an init script.</a><br/>
117 <a href="#C7">C7. How can I forward mail to another
121 <h2 id="C_T">How to make fetchmail play nice with various MTAs</h2>
123 <a href="#T1">T1. How can I use fetchmail with sendmail?</a><br/>
124 <a href="#T2">T2. How can I use fetchmail with qmail?</a><br/>
125 <a href="#T3">T3. How can I use fetchmail with exim?</a><br/>
126 <a href="#T4">T4. How can I use fetchmail with smail?</a><br/>
127 <a href="#T5">T5. How can I use fetchmail with SCO's MMDF?</a><br/>
128 <a href="#T6">T6. How can I use fetchmail with Lotus Notes?</a><br/>
129 <a href="#T7">T7. How can I use fetchmail with Courier IMAP?</a><br/>
130 <a href="#T8">T8. How can I use fetchmail with vbmailshield?</a><br/>
132 <h2 id="C_S">How to make fetchmail work with various servers</h2>
134 <a href="#S1"><strike>S1. How can I use fetchmail with qpopper?</strike></a><br/>
135 <a href="#S2">S2. How can I use fetchmail with Microsoft Exchange?</a><br/>
136 <a href="#S3">S3. How can I use fetchmail with HP OpenMail?</a><br/>
137 <a href="#S4">S4. How can I use fetchmail with Novell GroupWise?</a><br/>
138 <a href="#S5">S5. How can I use fetchmail with InterChange?</a><br/>
139 <a href="#S6">S6. How can I use fetchmail with MailMax?</a><br/>
140 <a href="#S7">S7. How can I use fetchmail with FTGate?</a><br/>
142 <h2 id="C_I">How to fetchmail work with specific ISPs</h2>
144 <a href="#I1">I1. How can I use fetchmail with Compuserve RPA?</a><br/>
145 <a href="#I2">I2. How can I use fetchmail with Demon Internet's SDPS?</a><br/>
146 <a href="#I3">I3. How can I use fetchmail with usa.net's servers?</a><br/>
147 <a href="#I4">I4. How can I use fetchmail with geocities POP3 servers?</a><br/>
148 <a href="#I5">I5. How can I use fetchmail with Hotmail or Lycos Webmail?</a><br/>
149 <a href="#I6">I6. How can I use fetchmail with MSN?</a><br/>
150 <a href="#I7">I7. How can I use fetchmail with SpryNet?</a><br/>
151 <a href="#I8">I8. How can I use fetchmail with comcast.net or other
152 Maillennium servers?</a><br/>
153 <a href="#I9">I9. How can I use fetchmail with GMail/Google Mail?</a><br/>
155 <h2 id="C_K">How to set up well-known security and authentication
158 <a href="#K1">K1. How can I use fetchmail with SOCKS?</a><br/>
159 <a href="#K2">K2. How can I use fetchmail with IPv6 and IPsec?</a><br/>
160 <a href="#K3">K3. How can I get fetchmail to work with ssh?</a><br/>
161 <a href="#K4">K4. What do I have to do to use the IMAP-GSS protocol?</a><br/>
162 <a href="#K5">K5. How can I use fetchmail with SSL?</a><br/>
163 <a href="#K6">K6. How can I tell fetchmail not to try TLS if the server
164 advertises it? Why does fetchmail use SSL even though not configured?</a><br/>
166 <h2 id="C_R">Runtime fatal errors</h2>
168 <a href="#R1">R1. Fetchmail isn't working, and -v shows 'SMTP
169 connect failed' messages.</a><br/>
170 <a href="#R2">R2. When I try to configure an MDA, fetchmail doesn't
172 <a href="#R3">R3. Fetchmail dumps core when given an invalid rc
174 <a href="#R4"><strike>R4. Fetchmail dumps core in -V mode, but operates
175 normally otherwise.</strike></a><br/>
176 <a href="#R5">R5. Running fetchmail in daemon mode doesn't
178 <a href="#R6">R6. Fetchmail randomly dies with socket errors.</a><br/>
179 <a href="#R7">R7. Fetchmail running as root stopped working after
180 an OS upgrade</a><br/>
181 <a href="#R8">R8. Fetchmail is timing out after fetching certain
182 messages but before deleting them</a><br/>
183 <a href="#R9">R9. Fetchmail is timing out during message fetches</a><br/>
184 <a href="#R10"><strike>R10. Fetchmail is dying with SIGPIPE.</strike></a><br/>
185 <a href="#R11">R11. My server is hanging or emitting errors on CAPA.</a><br/>
186 <a href="#R12">R12. Fetchmail isn't working and reports getaddrinfo
188 <a href="#R13">R13. What does "Interrupted system call" mean?</a>
190 <h2 id="C_H">Hangs and lockups</h2>
192 <a href="#H1">H1. Fetchmail hangs when used with pppd.</a><br/>
193 <a href="#H2">H2. Fetchmail hangs during the MAIL FROM
195 <a href="#H3">H3. Fetchmail hangs while fetching mail.</a><br/>
198 <h2 id="C_D">Disappearing mail</h2>
200 <a href="#D1">D1. I think I've set up fetchmail correctly, but I'm
201 not getting any mail.</a><br/>
202 <a href="#D2">D2. All my mail seems to disappear after a dropped
204 <a href="#D3">D3. Mail that was being fetched when I interrupted my
205 fetchmail seems to have been vanished.</a><br/>
208 <h2 id="C_M">Multidrop-mode problems</h2>
210 <a href="#M1">M1. I've declared local names, but all my multidrop
211 mail is going to root anyway.</a><br/>
212 <a href="#M2">M2. I can't seem to get fetchmail to route to a local
213 domain properly.</a><br/>
214 <a href="#M3">M3. I tried to run a mailing list using multidrop,
215 and I have a mail loop!</a><br/>
216 <a href="#M4"><strike>M4. My multidrop fetchmail seems to be having DNS
217 problems.</strike></a><br/>
218 <a href="#M5">M5. I'm seeing long DNS delays before each message is
220 <a href="#M6">M6. How do I get multidrop mode to work with
222 <a href="#M7">M7. Multidrop mode isn't parsing envelope addresses
223 from my Received headers as it should.</a><br/>
224 <a href="#M8">M8. Users are getting multiple copies of
228 <h2 id="C_X">Mangled mail</h2>
230 <a href="#X1">X1. Spurious blank lines are appearing in the headers
231 of fetched mail.</a><br/>
232 <a href="#X2">X2. My mail client can't see a Subject
234 <a href="#X3">X3. Messages containing "From" at start of line are
235 being split.</a><br/>
236 <a href="#X4">X4. My mail is being mangled in a new and different
238 <a href="#X5"><strike>X5. Using POP3, retrievals seems to be fetching too
239 much!</strike></a><br/>
240 <a href="#X6">X6. My mail attachments are being dropped or
242 <a href="#X7">X7. Some mail attachments are hanging
244 <a href="#X8">X8. A spurious ) is being appended to my
246 <a href="#X9">X9. Missing "Content-Transfer-Encoding" header
247 with Domino IMAP</a><br/>
248 <h2 id="C_O">Other problems</h2>
250 <a href="#O1">O1. The --logfile option doesn't work if the logfile
251 doesn't exist.</a><br/>
252 <a href="#O2">O2. Every time I get a POP or IMAP message the header
253 is dumped to all my terminal sessions.</a><br/>
254 <a href="#O3">O3. Does fetchmail reread its rc file every poll
256 <a href="#O4">O4. Why do deleted messages show up again when I take
257 a line hit while downloading?</a><br/>
258 <a href="#O5">O5. Why is fetched mail being logged with my name,
259 not the real From address?</a><br/>
260 <a href="#O6">O6. I'm seeing long sendmail delays or hangs near the
261 start of each poll cycle.</a><br/>
262 <a href="#O7">O7. Why doesn't fetchmail deliver mail in date-sorted
264 <a href="#O8">O8. I'm using pppd. Why isn't my monitor option
266 <a href="#O9">O9. Why does fetchmail keep retrieving the same
267 messages over and over?</a><br/>
268 <a href="#O10"><strike>O10. Why is the received date on all my messages the
269 same?</strike></a><br/>
270 <a href="#O11">O11. I keep getting messages that say "Repoll
271 immediately" in my logs.</a><br/>
272 <a href="#O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a><br/>
273 <a href="#O13">O13. I want timestamp information in my fetchmail logs.</a><br/>
274 <a href="#O14">O14. Fetchmail no longer deletes oversized mails with
276 <a href="#O15">O15. Fetchmail always retains the first message in the
278 <a href="#O16">O16. Why is the Fetchmail FAQ only available in
279 ISO-216 A4 format? How do I get the FAQ in Letter
283 <h1 id="G">General problems</h1>
284 <h2><a id="G1" name="G1">G1. What is fetchmail and why should I
287 <p>Fetchmail is a one-stop solution to the remote mail retrieval
288 problem for Unix machines, quite useful to anyone with an
289 intermittent or dynamic-IP connection to a remote mailserver, SLIP or
290 PPP dialup, or leased line when SMTP isn't desired. Fetchmail can
291 collect mail using any variant of POP or IMAP and forwards to a the
292 local SMTP (via TCP socket) or LMTP (via TCP or Unix socket) listener or
293 into an MDA program, enabling all the normal
294 forwarding/filtering/aliasing mechanisms that would apply to local mail
295 or mail arriving via a full-time TCP/IP connection.</p>
297 <p>Fetchmail is not a toy or a coder's learning exercise, but an
298 industrial-strength tool capable of transparently handling every
299 retrieval demand from those of a simple single-user ISP connection
300 up to mail retrieval and rerouting for an entire client domain.
301 Fetchmail is easy to configure, unobtrusive in operation, powerful,
302 feature-rich, and well documented.</p>
304 <p>Fetchmail is <a href="http://www.opensource.org/">Open Source</a>
305 Software. The openness of the sources enables you to review and
306 customize the code, and contribute your changes.</p>
308 <p>A former fetchmail maintainer once claimed that Open Source software
309 were the strongest quality assurance, but the current maintainers do not
310 believe that open source alone is a criterion for quality – <a
311 href="fetchmail-SA-2005-01.txt">the remotely exploitable POP3
312 vulnerability (CVE-2005-2335)</a> lingered undiscovered in
313 fetchmail's code for years, which is a hint that open source code does
314 not audit itself.</p>
316 <p>Fetchmail is licensed under the <a
317 href="http://www.gnu.org/copyleft/gpl.html">GNU General Public
320 <p>If you found this FAQ in the distribution, see the README for
321 fetchmail's full feature list.</p>
323 <h2><a id="G2" name="G2">G2. Where do I find the latest FAQ and
324 fetchmail sources?</a></h2>
326 <p>The latest HTML FAQ is available alongside the latest fetchmail
327 sources at the fetchmail home page: <a
328 href="http://www.fetchmail.info/">http://www.fetchmail.info/</a>.
329 You can also usually find both in the <a
330 href="http://www.ibiblio.org/pub/Linux/system/mail/pop/!INDEX.short.html">
331 POP mail tools directory on iBiblio</a>.</p>
333 <p>A text dump of this FAQ is included in the fetchmail
334 distribution. Because it freezes at distribution release time, it
335 may not be completely current.</p>
337 <h2><a id="G3" name="G3">G3. Something does not work/I think I've found a bug. Will you fix it?</a></h2>
339 <p>The first thing you should to is to upgrade to the newest version of
340 fetchmail, and then see if the problem reproduces. So you'll probably
341 save us both time if you upgrade and test with <a href="#G2">the latest
342 version</a> <em>before</em> sending in a bug report.</p>
344 <p>Bugs will be fixed, provided you include enough diagnostic information
345 for me to go on. Send bugs to <a
346 href="mailto:fetchmail-users@lists.berlios.de">fetchmail-users</a>.
347 When reporting bugs, please include the following:</p>
350 <li>Your operating system.</li>
352 <li>Your compiler version, if you built from source; otherwise, the
353 name and origin of the RPM or other binary package you
356 <li>The name and version of the SMTP listener or MDA you are
359 <li>Any command-line options you used.</li>
361 <li>The output of <kbd>env LC_ALL=C fetchmail -V</kbd> called with
362 whatever other command-line options you used.</li>
364 <li><strong>The output of <kbd>env LC_ALL=C fetchmail --nodetach -vvv
365 --nosyslog</kbd> with whatever other command-line options you use
367 <p>It is very important that the transcript include your
368 POP/IMAP server's greeting line, so I can identify it in case of server
369 problems. This transcript will not reveal your passwords, which are
370 specially masked out precisely so transcripts can be passed around.</p>
374 <p>If you have FTP access to your remote mail account, and you have
375 any suspicion that the bug was triggered by a particular message,
376 please include a copy of the message that triggered the bug.</p>
378 <p>If your bug is something that used to work but stopped working
379 when you upgraded, then you can help pin the bug down by trying <a
380 href="http://download.berlios.de/fetchmail/">intermediate versions
381 of fetchmail</a> until you identify the revision that broke your
382 feature. The smart way to do this is by binary search on the
383 version sequence. First, try the version halfway between your last
384 good one and the current one. If it works, the failure was
385 introduced in the upper half of the sequence; if it doesn't, the
386 failure was introduced in the lower half. Now bisect that half in
387 the same way. In a very few tries, you should be able to identify
388 the exact adjacent pair of versions between which your bug was
389 introduced. <STRONG>Please</STRONG> include session transcripts (as
390 described in the last bullet point above) of <strong>both
391 the working and failing versions.</strong> Often, the source of the problem
392 can instantly identified by looking at the differences in protocol
395 <p>It may helpful if you include your .fetchmailrc file, but not
396 necessary unless your symptom seems to involve an error in
397 configuration parsing. If you do send in your .fetchmailrc, mask
398 the passwords first! Otherwise, fetchmail -V – as directed above
399 – will usually suffice.</p>
401 <p>If fetchmail seems to run and fetch mail, but the headers look
402 mangled (that is, headers are missing or blank lines are inserted
403 in the headers) then read the FAQ items in section <a
404 href="#X1">X</a> before submitting a bug report. Pay special
405 attention to the item on <a href="#generic_mangling">diagnosing
406 mail mangling</a>. There are lots of ways for other programs in the
407 mail chain to screw up that look like fetchmail's fault, but you
408 may be able to fix these by tweaking your configuration.</p>
410 <p>If the bug involves a core dump or hang, a gdb stack trace is
411 good to have. (Bear in mind that you can attach gdb to a running
412 but hung process by giving the process ID as a second argument.)
413 You will need to reconfigure with:</p>
416 CFLAGS=-g LDFLAGS=" " ./configure
419 <p>Then rebuild in order to generate a version that can be
420 traced with a debugger such as gdb, dbx or idb.</p>
422 <p>Best of all is a mail file which, when fetched, will reproduce
423 the bug under the latest (current) version.</p>
425 <p>Any bug I can reproduce will usually get fixed quite quickly.
426 Bugs I can't reproduce are a crapshoot. If the solution isn't obvious
427 when I first look, it may evade me for a long time (or to put it another
428 way, fetchmail is well enough tested that the easy bugs have long since
429 been found). So if you want your bug fixed rapidly, it is not just
430 sufficient but <em>necessary</em> that you give me a way to
431 easily reproduce it.</p>
433 <h2><a id="G4" name="G4">G4. I have this idea for a neat feature.
434 Will you add it?</a></h2>
436 <p>If it's reasonable for fetchmail and cannot be solved with reasonable
437 effort outside of fetchmail, perhaps.</p>
439 <p>You can do spam filtering better with procmail or maildrop on
440 the server side and (if you're the server sysadmin) sendmail.cf
441 domain exclusions. If you really want fetchmail to do it from the
442 client side, use a <code>preconnect</code> command to call
443 <a href='http://mailfilter.sourceforge.net/'>mailfilter</a>.</p>
445 <p>You can do other policy things better with the
446 <code>mda</code> option and script wrappers around fetchmail. If
447 it's a prime-time-vs.-non-prime-time issue, ask yourself whether a
448 wrapper script called from crontab would do the job.</p>
450 <p>fetchmail's first job is transport though, and it should do this
451 well. If a feature would cause fetchmail to deteriorate in other
452 respects, the feature will probably not be added.</p>
454 <p>For reasons fetchmail doesn't have other commonly-requested
455 features (such as password encryption, or multiple concurrent polls
456 from the same instance of fetchmail) see <a
457 href="esrs-design-notes.html">ESR's design
458 notes</a>. Note that this document is partially obsoleted by the
459 <a href="design-notes.html">updated design notes.</a></p>
461 <h2><a id="G5" name="G5">G5. I want to make fetchmail remove kept mail after
464 <p>The second-most-requested feature for fetchmail, after
465 content-based filtering, is the ability to have it remove messages
466 from a maildrop after N days, typically to be used with the
467 <code>keep</code> option. Several messaging programs with graphical
468 user interface support this feature.</p>
470 <p>This feature is not yet implemented. It may be at a future date,
471 spare time of developers permitting.</p>
473 <p>For the time being, the contrib/ directory contains some <em>unsupported</em>
474 tools that may help, namely mold-remover.py and delete-later.</p>
476 <h2><a id="G6" name="G6">G6. Is there a mailing list for exchanging
479 <p>There is a fetchmail-users list
480 <fetchmail-users@lists.berlios.de>
481 for bug reports and people who want to discuss configuration issues of
482 fetchmail. It's a Mailman list, see <a
483 href="http://lists.berlios.de/mailman/listinfo/fetchmail-users">http://lists.berlios.de/mailman/listinfo/fetchmail-users</a>.</p>
484 <p>There is a fetchmail-devel list
485 <fetchmail-devel@lists.berlios.de> for people who want to discuss
486 fixes and improvements in fetchmail and help co-develop it. It's a
487 Mailman list, which you can sign up for at <a
488 href="http://lists.berlios.de/mailman/listinfo/fetchmail-devel">http://lists.berlios.de/mailman/listinfo/fetchmail-devel</a>.
489 There is also an announcements-only list,
490 <fetchmail-announce@lists.berlios.de>, which you can sign up for at <a
491 href="http://lists.berlios.de/mailman/listinfo/fetchmail-announce">http://lists.berlios.de/mailman/listinfo/fetchmail-announce</a>.</p>
493 <h2><a id="G7" name="G7">G7. So, what's this I hear about a
494 fetchmail paper?</a></h2>
496 <p>Eric S. Raymond also considered fetchmail development a sociological
497 experiment, an extended test to see if my theory about the critical
498 features of the Linux development model is correct.</p>
500 <p>He considers the experiment a success. He wrote a paper about it titled <a
501 href="http://www.catb.org/~esr/writings/cathedral.html">The
502 Cathedral and the Bazaar</a> which was first presented at Linux
503 Kongress '97 in Bavaria and very well received there. It was also
504 given at Atlanta Linux Expo, Linux Pro '97 in Warsaw, and the first
505 Perl Conference, at UniForum '98, and was the basis of an invited
506 presentation at Usenix '98. The folks at Netscape told ESR it helped
508 href="http://wp.netscape.com/newsref/pr/newsrelease558.html">give
509 away the source for Netscape Communicator</a>.</p>
511 <p>If you're reading a non-HTML dump of this FAQ, you can find the
512 paper on the Web with a search for that title.</p>
514 <h2><a id="G8" name="G8">G8. What is the best server to use with
517 <p>Fetchmail will work with any POP, IMAP, ETRN, or ODMR server
518 that conforms to the relevant standards/RFCs (and even some outright
519 broken ones like <a href="#S2">Microsoft Exchange</a> and <a
520 href="#S6">Novell GroupWise</a>). This doesn't mean it works equally
521 well with all, however. POP2 servers, and POP3 servers without UIDL,
522 limit fetchmail's capabilities in various ways described on the manual
525 <p>Most modern Unixes (and effectively all Linux/*BSD systems) come
526 with POP3 support preconfigured (but beware of the horribly broken
527 POP3 server mentioned in <a href="#D2">D2</a>). An increasing
528 minority also feature IMAP (you can detect IMAP support by using the
529 'Probe for supported protocols' function in the fetchmailconf
530 utility - unfortunately it does not detect SSL-wrapped variants).</p>
532 <p>If you have the option, we recommend using or installing an
533 IMAP4rev1 or UIDL- and TOP-capable POP3 server. IMAP enables some
534 significant performance optimizations.</p>
536 <p>Don't be fooled by NT/Exchange propaganda. M$ Exchange is just
537 plain broken (see item <a href="#S2">S2</a>) and NT cannot handle
538 the sustained load of a high-volume remote mail server. Even
539 Microsoft itself knows better than to try this; their own Hotmail
540 service runs over Solaris! For extended discussion, see John
541 Kirch's excellent <a href="http://unix-vs-nt.org/kirch/">white
542 paper</a> on Unix vs. NT performance.</p>
544 <p>A decent POP3/IMAP server that has recently become popular is <a
545 href="http://dovecot.org/">Dovecot</a>.</p>
547 <p>Avoid <a href="http://home.pages.de/~mandree/qmail-bugs.html">qmail,
548 it's broken and unmaintained.</a></p>
550 <h2><a id="G9" name="G9">G9. What is the best mail program to use
551 with fetchmail?</a></h2>
553 <p>Fetchmail will work with all popular <a href="#T1">mail
554 transport programs</a>. It also doesn't care which user agent you
555 use, and user agents are as a rule almost equally indifferent to
556 how mail is delivered into your system mailbox. So any of the
557 popular Unix mail agents – <a
558 href="http://www.instinct.org/elm/">elm</a>, <a
559 href="http://www.washington.edu/pine/">pine</a>, <a
560 href="http://www.cs.indiana.edu/docproject/mail/mh.html">mh</a>, or
561 <a href="http://www.mutt.org">mutt</a> – will work fine with
564 <p>All this having been said, I can't resist putting in a discreet
565 plug for <a href="http://www.mutt.org">mutt</a>. Mutt's interface
566 is only a little different from that of its now-moribund ancestor
567 elm, but its flexibility and excellent handling of MIME and PGP put it
568 in a class by itself. You won't need its built-in POP3 support, though.
571 <h2><a id="G10" name="G10">G10. How can I avoid sending my password
574 <p>Depending on what your mail server you are talking to, this
575 ranges from trivial to impossible. It may even be next to
578 <p>In general there is little point in trying to secure your fetchmail
579 transaction unless you trust the security of the server host you are
580 retrieving mail from. Your vulnerability is more likely to be an
581 insecure local network on the server end (e.g. to somebody with a
582 TCP/IP packet sniffer intercepting Ethernet traffic between the modem
583 concentrator or DSL POP you dial in to and the mailserver host).</p>
585 <p>Having realized this, you need to ask whether password
586 encryption alone will really address your security exposure. If you
587 think you might be snooped between server and client, it's better
588 to use end-to-end encryption such as GnuPG (see below) on your whole
589 mail stream so none of it can be read. One of the advantages of
590 fetchmail over conventional SMTP-push delivery is that you may be able
591 to arrange encryption by using ssh(1); see <a href="#K3">K3</a>.</p>
593 <p>Note that ssh is not a complete privacy solution either, as your
594 mail could have been snooped in transit to your POP server from
595 wherever it originated. For best security, agree with your
596 correspondents to use a tool such as <a
597 href="http://www.gnupg.org/">GnuPG</a> (Gnu Privacy Guard) or PGP
598 (Pretty Good Privacy).</p>
600 <p>If ssh/sshd isn't available, or you find it too complicated for
601 you to set up, password encryption will at least keep a malicious
602 cracker from deleting your mail, and require him to either tap your
603 connection continuously or crack root on the server in order to
606 <p>You can deduce what encryptions your mail server has available
607 by looking at the server greeting line (and, for IMAP, the response
608 to a CAPABILITY query). Do a <code>fetchmail -v</code> to see
609 these, or telnet direct to the server port (110 for POP3, 143 for
612 <p>If your mailserver is using IMAP 2000, it'll have CRAM-MD5
613 support built in. Fetchmail autodetects this; you can skip the rest
616 <p>The POP3 facility you are most likely to have available is APOP.
617 This is a POP3 feature supported by many servers (fetchmailconf's
618 autoprobe facility will detect it and tell you if you have it). If
619 you see something in the greeting line that looks like an
620 angle-bracket-enclosed Internet address with a numeric left-hand
621 part, that's an APOP challenge (it will vary each time you log in).
622 For some hosts, you need to register a secret on the host (using
623 <code>popauth(8)</code> or some program like that). Specify the
624 secret as your password in your .fetchmailrc; it will be used to
625 encrypt the current challenge, and the encrypted form will be sent
626 back the the server for verification. Note that APOP is no longer
627 considered secure since March 2007.</p>
629 <p>Alternatively, you may have Kerberos available. This may require
630 you to set up some magic files in your home directory on your
631 client machine, but means you can omit specifying any password at
634 <p>Fetchmail supports two different Kerberos schemes. One is a POP3
635 variant called KPOP; consult the documentation of your mail server
636 to see if you have it (one clue is the string "krb-IV" in the
637 greeting line on port 110). The other is an IMAP and POP3 facility
638 described by RFC1731 and RFC1734. You can tell if this one is
639 present by looking for AUTH=KERBEROS_V4 in the CAPABILITY
642 <p>If you are fetching mail from a CompuServe POP3 account, you can
643 use their RPA authentication. See <a href="#I1">I1</a> for details.
644 If you are fetching mail from
645 Microsoft Exchange using IMAP, you will be able to use NTLM.</p>
647 <p>Your POP3 server may have the RFC1938 OTP capability to use
648 one-time passwords (if it doesn't, you can get OTP patches for the
649 2.2 version of the Qualcomm popper from <a href="#cmetz">Craig
650 Metz</a>). To check this, look for the string "otp-" in the
651 greeting line. If you see it, and your fetchmail was built with
652 OPIE support compiled in (see the distribution INSTALL file),
653 fetchmail will detect it also. When using OTP, you will specify a
654 password but it will not be sent en clair.</p>
656 <p>You can get both POP3 and IMAP OTP patches from <a id="cmetz"
657 name="cmetz">Craig Metz</a> at <a
658 href="http://www.inner.net/opie">http://www.inner.net/opie</a>.</p>
660 <p>These patches use a SASL authentication method named "X-OTP"
661 because there is not currently a standard way to do this; fetchmail
662 also uses this method, so the two will interoperate happily. They
663 better, because this is how Craig gets his mail ;-)</p>
665 <p>Finally, you can use <a href="#K5">SSL</a> for complete
666 end-to-end encryption if you have an SSL-enabled mailserver.</p>
668 <h2><a id="G11" name="G11">G11. Is any special configuration needed
669 to use a dynamic IP address?</a></h2>
671 <p>Yes. In order to avoid giving indigestion to certain picky MTAs
672 (notably <a href="#T3">exim</a>), fetchmail always makes the RCPT TO
673 address it feeds the MTA a fully qualified one with a hostname
674 part. Normally it does this by appending @ and "localhost", but
675 when you are using Kerberos or ETRN mode it will append @ and your
676 machine's fully-qualified domain name (FQDN).</p>
678 <p>Appending the FQDN can create problems when fetchmail is running
679 in daemon mode and outlasts the dynamic IP address assignment your
680 client machine had when it started up.</p>
682 <p>Since the new IP address (looked up at RCPT TO interpretation
683 time) doesn't match the original, the most benign possible result
684 is that your MTA thinks it's seeing a relaying attempt and refuses.
685 More frequently, fetchmail will try to connect to a nonexistent
686 host address and time out. Worst case, you could up forwarding your
687 mail to the wrong machine!</p>
689 <p>Use the <code>smtpaddress</code> option to force the appended
690 hostname to one with a (fixed) IP address of 127.0.0.1 in your
691 <code>/etc/hosts</code>. (The name 'localhost' will usually work;
692 or you can use the IP address itself.)</p>
694 <p>Only one fetchmail option interacts directly with your IP
695 address, '<code>interface</code>'. This option can be used to set
696 the gateway device and restrict the IP address range fetchmail will
697 use. Such a restriction is sometimes useful for security reasons,
698 especially on multihomed sites. See <a href="#C3">C3</a>.</p>
700 <p>I recommend against trying to set up the <code>interface</code>
701 option when initially developing your poll configuration – it's
702 never necessary to do this just to get a link working. Get the link
703 working first, observe the actual address range you see on
704 connections, and add an <code>interface</code> option (if you need
707 <p>You can't use ETRN if you have a dynamic IP address (your ISP
708 changes your IP address occasionally, possibly with every connect).
709 You need to have your own registered domain and a definite IP
710 address registered for that domain. The server needs to be
711 configured to accept mail for your domain but then queue it to
712 forward to your machine. ETRN just tells to server to flush its
713 queue for your domain. Fetchmail doesn't actually get the mail in
716 <p>You can use On-Demand Mail Relay (ODMR) with a dynamic IP
717 address; that's what it was designed for, and it provides
718 capabilities very similar to ETRN. Unfortunately ODMR servers are
719 still not yet widely deployed, as of 2006.</p>
721 <p>If you're using a dynamic-IP configuration, one other
722 (non-fetchmail) problem you may run into with outgoing mail is that
723 some sites will bounce your email because the hostname you're giving
724 them isn't real (and doesn't match what they get doing a reverse
725 DNS on your dynamically-assigned IP address). If this happens, you
726 need to hack your sendmail so it masquerades as your host.
733 <p>in your <code>sendmail.cf</code> will work, or you can set</p>
736 MASQUERADE_AS(smarthost.here)
739 <p>in the m4 configuration and do a reconfigure. (In both cases,
740 replace <code>smarthost.here</code> with the actual name of your
741 mailhost.) See the <a
742 href="http://www.lege.com/sendmail-FAQ.txt">sendmail FAQ</a> for
745 <h2><a id="G12" name="G12">G12. Is any special configuration needed
746 to use firewalls?</a></h2>
748 <p>No. You can use fetchmail with SOCKS, the standard tool for
749 indirecting TCP/IP through a firewall. You can find out about
750 SOCKS, and download the SOCKS software including server and client
751 code, at the <a href="http://www.socks.nec.com/">SOCKS distribution
754 <p>The specific recipe for using fetchmail with a firewall is at <a
755 href="#K1">K1</a></p>
757 <h2><a id="G13" name="G13">G13. Is any special configuration needed
758 to <em>send</em> mail?</a></h2>
760 <p>A user asks: but how do we send mail out to the POP3 server? Do
761 I need to implement another tool or will fetchmail do this too?</p>
763 <p>Fetchmail only handles the receiving side. The sendmail or other
764 preinstalled MTA on your client machine will handle sending mail
765 automatically; it will ship mail that is submitted while the
766 connection is active, and put mail that is submitted while the
767 connection is inactive into the outgoing queue.</p>
769 <p>Normally, sendmail is also run periodically (every 15 minutes on
770 most Linux systems) in a mode that tries to ship all the mail in
771 the outgoing queue. If you have set up something like pppd to
772 automatically dial out when your kernel is called to open a TCP/IP
773 connection, this will ensure that the mail gets out.</p>
775 <h2><a id="G14" name="G14">G14. Is fetchmail
776 Y2K-compliant?</a></h2>
778 <p>Fetchmail is fully Y2K-compliant.</p>
780 <p>Fetchmail could theoretically have problems when the 32-bit
781 time_t counters roll over in 2038, but I doubt it. Timestamps
782 aren't used for anything but log entry generation. Anyway, if you
783 aren't running on a 64-bit machine by then, you'll deserve to
786 <h2><a id="G15" name="G15">G15. Is there a way in fetchmail to
787 support disconnected IMAP mode?</a></h2>
789 <p>No. Fetchmail is a mail transport agent, best understood as a
790 protocol gateway between POP3/IMAP servers and SMTP. Disconnected
791 operation requires an elaborate interactive client. It's a very
792 different problem.</p>
794 <h2><a id="G16" name="G16">G16. How will fetchmail perform under
795 heavy loads?</a></h2>
797 <p>Fetchmail streams message bodies line-by-line; the most core it
798 ever requires per message is enough memory to hold the RFC822
799 header, and that storage is freed when body processing begins. It
800 is, accordingly, quite economical in its use of memory. It will store
801 the UID or UIDL data in core however, which can become considerable if
802 you are keeping lots of messages on the server.</p>
804 <p>After startup time, a fetchmail running in daemon mode stats its
805 configuration file once per poll cycle to see whether it has
806 changed and should be rescanned. Other than that, a fetchmail in
807 normal operation doesn't touch the disk at all; that job is left up
808 to the MTA or MDA the fetchmail talks to.</p>
810 <p>Fetchmail's performance is usually bottlenecked by latency on
811 the POP server or (less often) on the TCP/IP link to the server.
812 This is not a problem readily solved by tuning fetchmail, or even
813 by buying more TCP/IP capacity (which tends to improve bandwidth
814 but not necessarily latency).</p>
817 <h1>Build-time problems</h1>
818 <h2><a id="B1" name="B1"><strike>B1. Make coughs and dies when building on
819 FreeBSD.</strike></a></h2>
821 <p style="font-style:italic;">As of release 6.3.0, fetchmail's
822 Makefile[.in] should work flawlessly with BSD's portable make used on
823 FreeBSD. With older releases, use GNU make (usually installed as
824 <code>gmake</code>; otherwise try <kbd>pkg_add -r gmake</kbd>).</p>
826 <h2><a id="B2" name="B2">B2. Lex bombs out while building the
827 fetchmail lexer.</a></h2>
829 <p>fetchmail 6.3.0 and newer ship with the lexer and parser in .c
830 formats, so you do not need to use lex unless you hacked the .l or .y
833 <p>fetchmail's lexer has been developed with GNU flex and uses some of
834 its specialties, so the lexer cannot be compiled with the lex tools
835 shipped by some UNIX vendors (HP, SGI, Sun).</p>
837 <h2><a id="B3" name="B3">B3. I get link failures when I try to
838 build fetchmail.</a></h2>
840 <p>If you get errors resembling these:</p>
843 mxget.o(.text+0x35): undefined referenceto '__res_search'
844 mxget.o(.text+0x99): undefined reference to '__dn_skipname'
845 mxget.o(.text+0x11c): undefined reference to '__dn_expand'
846 mxget.o(.text+0x187): undefined reference to '__dn_expand'
847 make: *** [fetchmail] Error 1
850 <p>then you must add "-lresolv" to the LOADLIBS line in your
851 Makefile once you have installed the 'bind' package.</p>
853 <p>If you get link errors involving <tt>dcgettext</tt>, like
857 rcfile_y.o: In function 'yyparse':
858 rcfile_y.o(.text+0x3aa): undefined reference to 'dcgettext__'
859 rcfile_y.o(.text+0x4f2): undefined reference to 'dcgettext__'
860 rcfile_y.o(.text+0x5ee): undefined reference to 'dcgettext__'
861 rcfile_y.o: In function 'yyerror':
862 rcfile_y.o(.text+0xc7c): undefined reference to 'dcgettext__'
863 rcfile_y.o(.text+0xcc8): undefined reference to 'dcgettext__'
864 rcfile_y.o(.text+0xdf9): more undefined references to 'dcgettext__' follow
867 <p>install an up to date version of GNU gettext, reconfigure and rebuild
868 fetchmail. If that does not help, reconfigure with '--disable-nls' added
869 to the "./configure" command and rebuild.</p>
871 <h2><a id="B4" name="B4">B4. I get build failures in the intl
874 <p>Reconfigure with <tt>--disable-nls</tt> and recompile.</p>
877 <h1>Fetchmail configuration file grammar questions</h1>
878 <h2><a id="F1" name="F1">F1. Why does my old .fetchmailrc file no
879 longer work?</a></h2>
881 <h3>If your file predates 6.3.0</h3>
883 <p>The <tt>netsec</tt> option was discontinued and needs to be
886 <h3>If your file predates 5.8.9</h3>
888 <p>If you were using ETRN mode, change your <tt>smtphost</tt>
889 option to a <tt>fetchdomains</tt> option.</p>
891 <h3>If your file predates 5.8.3</h3>
893 <p>The <tt>'via localhost'</tt> special case for use with ssh tunnelling is
894 gone. Use the <tt>%h</tt> feature of <tt>plugin</tt> instead.</p>
896 <h3>If your file predates 5.6.8</h3>
898 <p>In 5.6.8, the <tt>preauth</tt> keyword and option were changed
899 back to <tt>auth</tt>. The <tt>preauth</tt> synonym will still be
900 supported through a few more point releases.</p>
902 <h3>If your file predates 5.6.5</h3>
904 <p>The <tt>imap-gss</tt>, <tt>imap-k4</tt>, and <tt>imap-login</tt>
905 protocol types are gone. This is a result of a major re-factoring
906 of the authentication machinery; fetchmail can now use Kerberos V4
907 and GSSAPI not just with IMAP but with POP3 servers that have
908 RFC1734 support for the AUTH command.</p>
910 <p>When trying to identify you to an IMAP or POP mailserver,
911 fetchmail now first tries methods that don't require a password
912 (GSSAPI, KERBEROS_IV); then it looks for methods that mask your
913 password (CRAM-MD5, X-OTP); and only if it the server doesn't
914 support any of those will it ship your password en clair.</p>
916 <p>Setting the <tt>preauth</tt> option to any value other than
917 'password' will prevent from looking for a password in your
918 <tt>.netrc</tt> file or querying for it at startup time.</p>
920 <h3>If your file predates 5.1.0</h3>
922 <p>In 5.1.0, the <tt>auth</tt> keyword and option were changed to
923 <tt>preauth</tt>.</p>
925 <h3>If your file predates 4.5.5</h3>
927 <p>If the <code>dns</code> option is on (the default), you may need
928 to make sure that any hostname you specify (for mail hosts or for
929 an SMTP target) is a canonical fully-qualified hostname). In order
930 to avoid DNS overhead and complications, fetchmail no longer tries
931 to derive the fetchmail client machine's canonical DNS name at
934 <h3>If your file predates 4.0.6:</h3>
936 <p>Just after the '<code>via</code>' option was introduced, I
937 realized that the interactions between the '<code>via</code>',
938 '<code>aka</code>', and '<code>localdomains</code>' options were
939 out of control. Their behavior had become complex and confusing, so
940 much so that I was no longer sure I understood it myself. Users
941 were being unpleasantly surprised.</p>
943 <p>Rather than add more options or crock the code, I re-thought it.
944 The redesign simplified the code and made the options more
945 orthogonal, but may have broken some complex multidrop
948 <p>Any multidrop configurations that depended on the name just
949 after the '<code>poll</code>' or '<code>skip</code>' keyword being
950 still interpreted as a DNS name for address-matching purposes, even
951 in the presence of a '<code>via</code>' option, will break.</p>
953 <p>It is theoretically possible that other unusual configurations
954 (such as those using a non-FQDN poll name to generate Kerberos IV
955 tickets) might also break; the old behavior was sufficiently murky
956 that we can't be sure. If you think this has happened to you,
957 contact the maintainer.</p>
959 <h3>If your file predates 3.9.5:</h3>
961 <p>The '<code>remote</code>' keyword has been changed to
962 '<code>folder</code>'. If you try to use the old keyword, the
963 parser will utter a warning.</p>
965 <h3>If your file predates 3.9:</h3>
967 <p>It could be because you're using a .fetchmailrc that's written
968 in the old popclient syntax without an explicit
969 '<code>username</code>' keyword leading the first user entry
970 attached to a server entry.</p>
972 <p>This error can be triggered by having a user option such as
973 '<code>keep</code>' or '<code>fetchall</code>' before the first
974 explicit username. For example, if you write</p>
977 poll openmail protocol pop3
978 keep user "Hal DeVore" there is hdevore here
981 <p>the '<code>keep</code>' option will generate an entire user
982 entry with the default username (the name of fetchmail's invoking
985 <p>The popclient compatibility syntax was removed in 4.0. It
986 complicated the configuration file grammar and confused users.</p>
988 <h3>If your file predates 2.8:</h3>
990 <p>The '<code>interface</code>', '<code>monitor</code>' and
991 '<code>batchlimit</code>' options changed after 2.8.</p>
993 <p>They used to be global options with '<code>set</code>' syntax
994 like the batchlimit and logfile options. Now they're per-server
995 options, like '<code>protocol</code>'.</p>
997 <p>If you had something like</p>
1000 set interface = "sl0/10.0.2.15"
1003 <p>in your .fetchmailrc file, simply delete that line and insert
1004 'interface sl0/10.0.2.15' in the server options part of your
1005 'defaults' declaration.</p>
1007 <p>Do similarly for any '<code>monitor</code>' or
1008 '<code>batchlimit</code>' options.</p>
1010 <h2><a id="F2" name="F2">F2. The .fetchmailrc parser won't accept
1011 my all-numeric user name.</a></h2>
1013 <p>Either upgrade to a post-5.0.5 fetchmail or put string quotes
1016 <p>The configuration file parser in older fetchmail versions
1017 treated any all-numeric token as a number, which confused it when
1018 it was expecting a name. String quoting forces the token's
1021 <p>The lexical analyzer in 5.0.6 and beyond is smarter and assumes
1022 any token following "username" or "password" is a string.</p>
1024 <h2><a id="F3" name="F3">F3. The .fetchmailrc parser won't accept
1025 my host or username beginning with 'no'.</a></h2>
1027 <p>See <a href="#F2">F2</a>. You're caught in an unfortunate crack
1028 between the newer-style syntax for negated options ('no keep', 'no
1029 rewrite' etc.) and the older style run-on syntax ('nokeep',
1030 'norewrite' etc.).</p>
1032 <p>Upgrade to a 5.0.6 or later fetchmail, or put string quotes
1033 around your token.</p>
1035 <h2><a id="F4" name="F4">F4. I'm getting a 'parse error' message I
1036 don't understand.</a></h2>
1038 <p>The most common cause of mysterious parse errors is putting a
1039 server option after a user option. Check the manual page; you'll
1040 probably find that by moving one or more options closer to the
1041 'poll' keyword you can eliminate the problem.</p>
1043 <p>Yes, I know these ordering restrictions are hard to understand.
1044 Unfortunately, they're necessary in order to allow the 'defaults'
1045 feature to work.</p>
1048 <h1>Configuration questions</h1>
1049 <h2><a id="C1" name="C1">C1. Why do I need a .fetchmailrc when
1050 running as root on my own machine?</a></h2>
1052 <p>Ian T. Zimmerman <itz@rahul.net> asked:</p>
1054 <p>On the machine where I'm the only real user, I run fetchmail as
1055 root from a cron job, like this:</p>
1058 fetchmail -u "itz" -p POP3 -s bolero.rahul.net
1061 <p>This used to work as is (with no .fetchmailrc file in root's
1062 home directory) with the last version I had (1.7 or 1.8, I don't
1063 remember). But with 2.0, it RECPs all mail to the local root user,
1064 unless I create a .fetchmailrc in root's home directory
1068 skip bolero.rahul.net proto POP3
1072 <p>It won't work if the second line is just "<code>user
1073 itz</code>". This is silly.</p>
1075 <p>It seems fetchmail decides to RECP the 'default local user'
1076 (i.e. the uid running fetchmail) unless there are local aliases,
1077 and the 'default' aliases (itz->itz) don't count. They
1082 <p>No they shouldn't. I thought about this for a while, and I don't
1083 much like the conclusion I reached, but it's unavoidable. The
1084 problem is that fetchmail has no way to know, in general, that a
1085 local user 'itz' actually exists.</p>
1087 <p>"Ah!" you say, "Why doesn't it check the password file to see if
1088 the remote name matches a local one?" Well, there are two
1091 <p>One: it's not always possible. Suppose you have an SMTP host
1092 declared that's not the machine fetchmail is running on? You
1095 <p>Two: How do you know server itz and SMTP-host itz are the same
1096 person? They might not be, and fetchmail shouldn't assume they are
1097 unless local-itz can explicitly produce credentials to prove it
1098 (that is, the server-itz password in local-itz's .fetchmailrc
1101 <p>Once you start running down possible failure modes and thinking
1102 about ways to tinker with the mapping rules, you'll quickly find
1103 that all the alternatives to the present default are worse or
1104 unacceptably more complicated or both.</p>
1106 <h2><a id="C2" name="C2">C2. How can I arrange for a fetchmail
1107 daemon to get killed when I log out?</a></h2>
1109 <p>The easiest way to dispatch fetchmail on logout (which will work
1110 reliably only if you have just one login going at any time) is to
1111 arrange for the command 'fetchmail -q' to be called on logout.
1112 Under bash, you can arrange this by putting 'fetchmail -q' in the
1113 file '~/.bash_logout'. Most csh variants execute '~/.logout' on
1114 logout. For other shells, consult your shell manual page.</p>
1116 <p>Automatic startup/shutdown of fetchmail is a little harder to
1117 arrange if you may have multiple login sessions going. In the
1118 contrib subdirectory of the fetchmail distribution there is some
1119 shell code you can add to your .bash_login and .bash_logout
1120 profiles that will accomplish this. Thank James Laferriere
1121 <babydr@nwrain.net> for it.</p>
1123 <p>Some people start up and shut down fetchmail using the ppp-up
1124 and ppp-down scripts of pppd.</p>
1126 <h2><a id="C3" name="C3">C3. How do I know what interface and
1127 address to use with --interface?</a></h2>
1129 <p>This depends a lot on your local networking configuration (and
1130 right now you can't use it at all except under Linux and the newer
1131 BSDs). However, here are some important rules of thumb that can
1132 help. If they don't work, ask your local sysop or your Internet
1135 <p>First, you may not need to use --interface at all. If your
1136 machine only ever does SLIP or PPP to one provider, it's almost
1137 certainly by a point to point modem connection to your provider's
1138 local subnet that's pretty secure against snooping (unless someone
1139 can tap your phone or the provider's local subnet!). Under these
1140 circumstances, specifying an interface address is fairly
1143 <p>What the option is really for is sites that use more than one
1144 provider. Under these circumstances, typically one of your provider
1145 IP addresses is your mailserver (reachable fairly securely via the
1146 modem and provider's subnet) but the others might ship your packets
1147 (including your password) over unknown portions of the general
1148 Internet that could be vulnerable to snooping. What you'll use
1149 --interface for is to make sure your password only goes over the
1150 one secure link.</p>
1152 <p>To determine the device:</p>
1155 <li>If you're using a SLIP link, the correct device is probably
1158 <li>If you're using a PPP link, the correct device is probably
1161 <li>If you're using a direct connection over a local network such
1162 as an ethernet, use the command 'netstat -r' to look at your
1163 routing table. Try to match your mailserver name to a destination
1164 entry; if you don't see it in the first column, use the 'default'
1165 entry. The device name will be in the rightmost column.</li>
1168 <p>To determine the address and netmask:</p>
1171 <li>If you're talking to slirp, the correct address is probably
1172 10.0.2.15, with no netmask specified. (It's possible to configure
1173 slirp to present other addresses, but that's the default.)</li>
1175 <li>If you have a static IP address, run 'ifconfig <device>',
1176 where <device> is whichever one you've determined. Use the IP
1177 address given after "inet addr:". That is the IP address for your
1178 end of the link, and is what you need. You won't need to specify a
1181 <li>If you have a dynamic IP address, your connection IP will vary
1182 randomly over some given range (that is, some number of the least
1183 significant bits change from connection to connection). You need to
1184 declare an address with the variable bits zero and a complementary
1185 netmask that sets the range.</li>
1188 <p>To illustrate the rule for dynamic IP addresses, let's suppose
1189 you're hooked up via SLIP and your IP provider tells you that the
1190 dynamic address pool is 255 addresses ranging from 205.164.136.1 to
1191 205.164.136.255. Then</p>
1194 interface "sl0/205.164.136.0/255.255.255.0"
1197 <p>would work. To range over any value of the last two octets
1198 (65536 addresses) you would use</p>
1201 interface "sl0/205.164.0.0/255.255.0.0"
1204 <h2><a id="C4" name="C4">C4. How can I set up support for
1205 sendmail's anti-spam features?</a></h2>
1207 <p>This answer covers versions of sendmail from 8.9.3-20 (the
1208 version installed in Red Hat 6.2) upwards. If you have an older
1209 version, upgrade to sendmail 8.9.</p>
1211 <p>Stock sendmails can now do anti-spam exclusions based on a
1212 database of filter rules. The human-readable form of the database
1213 is at <tt>/etc/mail/access</tt>. The database itself is at
1214 <tt>/etc/mail/access.db</tt>.</p>
1216 <p>The table itself uses email addresses, domain names, and network
1217 numbers as keys. For example,</p>
1220 spammer@aol.com REJECT
1221 cyberspammer.com REJECT
1225 <p>would refuse mail from spammer@aol.com, any user from
1226 cyberspammer.com (or any host within the cyberspammer.com domain),
1227 and any host on the 192.168.212.* network. (This feature can be
1228 used to do other things as well; see the <a
1229 href="http://www.sendmail.org/m4/anti_spam.html">sendmail
1230 documentation</a> for details)</p>
1232 <p>To actually set up the database, run</p>
1235 makemap hash deny <deny
1238 <p>in /etc/mail.</p>
1240 <p>To test, send a message to your mailing address from that host
1241 and then pop off the message with fetchmail, using the -v argument.
1242 You can monitor the SMTP transaction, and when the FROM address is
1243 parsed, if sendmail sees that it is an address in spamlist,
1244 fetchmail will flush and delete it.</p>
1246 <p>Under no circumstances put your <strong>mailhost</strong> or
1247 <strong>any host you accept mail from</strong> using fetchmail into
1248 your reject file. You <strong>will</strong> lose mail if you do
1251 <h2><a id="C5" name="C5">C5. How can I poll some of my mailboxes
1252 more/less often than others?</a></h2>
1254 <p>Use the <cite>interval</cite> keyword on the ones that should be
1255 checked less often. For example, if you do a poll every 5 minutes,
1256 and want to poll some mailboxes every 5 minutes and some every 30
1257 minutes, use something like this:</p>
1260 poll mainsite.example.com proto pop3 user ....
1261 poll secondary.example.com proto pop3 interval 6 user ...
1264 <p>Then secondary.example.com will be polled every 6th time that
1265 mainsite.example.com is polled, which with a polling interval of
1266 every 5 minutes means that secondary.example.com will be polled
1267 every 30 minutes.</p>
1269 <h2><a id="C6" name="C6">C6. Fetchmail works OK started up manually,
1270 but not from an init script.</a></h2>
1272 <p>Often, startup scripts have a different environment than an
1273 interactive login shell. For instance, $HOME might point to "/root"
1274 when you are logged in as root, but it might be either unset, or
1275 set to "/" when the startup scripts are running. That means
1276 fetchmail at startup can't find the .fetchmailrc.</p>
1278 <p>Pick a location (such as /etc/fetchmailrc) and use fetchmail's
1279 -f option to point fetchmail at it. That should solve the
1282 <h2><a id="C7" name="C7">C7. How can I forward mail to another
1285 <p>To forward mail to a host other than the one you are running
1286 fetchmail on, use the <code>smtphost</code> or
1287 <code>smtpname</code> option. See the manual page for details.</p>
1290 <h1>How to make fetchmail play nice with various MTAs</h1>
1291 <h2><a id="T1" name="T1">T1. How can I use fetchmail with
1294 <p>For most sendmails, no special configuration is required. Eric
1295 Allman tells me that if <code>FEATURE(always_add_domain)</code> is
1296 included in sendmail's configuration, you can leave the
1297 <code>rewrite</code> option off.</p>
1299 <p>If your sendmail complains "sendmail does not relay", make
1300 sure your sendmail.cf file says <code>Cwlocalhost</code> so that
1301 sendmail recognizes 'localhost' as a name of its host.</p>
1303 <p>If you're mailing from another machine on your local network,
1304 also ensure that its IP address is listed in ip_allow or name in
1305 name_allow (usually in /etc/mail/)</p>
1307 <p>If you find that your sendmail doesn't like the address
1308 'FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail that
1309 fetchmail generates), you may have to set
1310 <code>FEATURE(accept_unqualified_senders)</code>.</p>
1312 <p>Günther Leber reports that Digital Unix sendmails won't
1313 work with fetchmail. The symptom is an error message "<code>553
1314 Local configuration error, hostname not recognized as
1315 local</code>". The problem is that fetchmail normally feeds
1316 sendmail with the client machine's host address in the MAIL FROM
1317 line. These sendmails think this means they're seeing the result of
1318 a mail loop and suppress the mail. You may be able to work around
1319 this by running in <code>--invisible</code> mode.</p>
1321 <p>If you want to support multidrop mode, and you can get access to
1322 your mailserver's sendmail.cf file, it's a good idea to add this
1326 H?l?Delivered-To: $h
1329 <p>This will cause the mailserver's sendmail to reliably write the
1330 appropriate envelope address into each message before fetchmail
1331 sees it, and tell fetchmail which header it is.  With this
1332 change, multidrop mode should work reliably even when the Received
1333 header omits the envelope address (which will typically be the case
1334 when the message has multiple recipients).  However it will
1335 still not distinguish the recipients, your only advantage is that
1336 no bounce will be sent if a message is BCC addressed to multiple
1337 users at your site.  To fix even that problem, you might want
1338 to try the following hack, which is however untested and quite
1342 H?J?Delivered-To: $u
1344 Mmdrop, P=/usr/bin/procmail, F=lsDFMqSPfhnu9J,
1345 S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP/HdrToSMTP,
1346 T=DNS/RFC822/X-Unix,
1347 A=procmail -Y -a $u -d $h
1350 <p>For both hacks, you have to declare '<code>envelope
1351 "Delivered-To:"</code>' on the fetchmail side, to put the virtual
1352 domain (e.g. 'domain.com') with RELAY permission into your access
1353 file and to add a line reading '<code>domain.com
1354 local:local-pop-user</code>' for the first and '<code>domain.com
1355 mdrop:local-pop-user</code>' for the second hack to your
1358 <p>You will notice that if the mail already has a Delivered-To
1359 header, sendmail will not add another.  Further, editing
1360 sendmail.cf directly is not very comfortable.  Solutions for
1361 both problems can be found in Peter 'Rattacresh' Backes' 'hybrid'
1362 patch against sendmail.  Have a look at it, you can find it in
1363 the contrib subdirectory.</p>
1365 <p>Feel free to try Martijn Lievaart's detailed recipe in the
1366 contrib subdirectory of the fetchmail source distribution, it
1367 attempts to realize multidrop mailboxes with an external
1370 <p>If for some reason you are invoking sendmail via the
1371 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
1372 don't forget to include the -i switch. Otherwise you will
1373 occasionally get mysterious delivery failures with a SIGPIPE as the
1374 sendmail instance dies. The problem is messages with a single dot
1375 at start of a text line.</p>
1377 <h2><a id="T2" name="T2">T2. How can I use fetchmail with
1380 <h3>qmail as your local SMTP server</h3>
1382 <p>Avoid <a href="http://home.pages.de/~mandree/qmail-bugs.html">qmail,
1383 it's broken and unmaintained.</a></p>
1385 <p>Turn on the <code>forcecr</code> option; qmail's listener mode
1386 doesn't like header or message lines terminated with bare
1388 (This information contributed by Robert de Bath
1389 <robert@mayday.cix.co.uk>.)</p>
1391 <h3>qmail as your ISP's POP3 server</h3>
1393 <p>Note that qmail's POP3 server, as of version 1.03 and netqmail 1.05,
1394 miscalculates the message sizes, so you may see size-related fetchmail
1397 <p>If a mailhost is using the qmail package, then it is usually possible
1398 to set up one fetchmail link to reliably collect the mail for an entire
1401 <p>One of the basic features of qmail is the 'Delivered-To:'
1402 message header. Whenever qmail delivers a message to a local
1403 mailbox it puts the username and hostname of the envelope recipient
1404 on this line. One major reason for this is to prevent mail
1405 loops, the other is to transport envelope information which is essential
1406 for multidrop (domain-in-a-mailbox) schemes.</p>
1408 <p>To set up qmail to batch mail for a disconnected site, the
1409 ISP-mailhost will have normally put that site in its 'virtualhosts'
1410 control file so it will add a prefix to all mail addresses for this
1411 site. This results in mail sent to
1412 'username@userhost.userdom.example.com' having a 'Delivered-To:' line
1416 Delivered-To: mbox-userstr-username@userhost.userdom.example.com
1419 <p>A single host maildrop will be slightly simpler:</p>
1422 Delivered-To: mbox-userstr-username@userhost.example.com
1425 <p>The ISP can make the 'mbox-userstr-' prefix anything they choose
1426 but a string matching the user host name is likely.</p>
1428 <p>To use this line you must:</p>
1431 <li>Ensure the option '<code>envelope "Delivered-To"</code>' is in the fetchmail
1434 <li>Ensure the option '<code>qvirtual "mbox-userstr-"</code>' is
1435 in the fetchmail config file, in order to remove this prefix from the
1436 username. (added by Luca Olivetti)</li>
1438 <li>Ensure you have a <code>localdomains</code> option containing
1439 '<code>userdom.example.com</code>' or '<code>userhost.userdom.example.com</code>'
1443 <h2><a id="T3" name="T3">T3. How can I use fetchmail with
1446 <p>If you have <code>rewrite</code> on:</p>
1448 <p>There is an RFC1123 requirement that MAIL FROM and RCPT TO
1449 addresses you pass to it have to be canonical (e.g. with a fully
1450 qualified hostname part). Therefore fetchmail tries to pass fully
1451 qualified RCPT TO addresses. But exim does not by default accept
1452 'localhost' as a fully qualified domain. This can be fixed.</p>
1454 <p>In exim.conf, add 'localhost' to your local_domains declaration
1455 if it's not already present. For example, the author's site at
1456 thyrsus.com would have a line reading:</p>
1459 local_domains = thyrsus.com:localhost
1462 <p>If you have <code>rewrite</code> off:</p>
1464 <p>MAIL FROM is a potential problem if the MTAs upstream from your
1465 fetchmail don't necessarily pass canonicalized From and Return-Path
1466 addresses, and fetchmail's <code>rewrite</code> option is off. The
1467 specific case where this has come up involves bounce messages
1468 generated by sendmail on your mailer host, which have the
1469 (un-canonicalized) origin address MAILER-DAEMON.</p>
1471 <p>The right way to fix this is to enable the <code>rewrite</code>
1472 option and have fetchmail canonicalize From and Return-Path
1473 addresses with the mailserver hostname before exim sees them. This
1474 option is enabled by default, so it won't be off unless you turned
1477 <p>If you must run with <code>rewrite</code> off, there is a switch
1478 in exim's configuration files that allows it to accept domainless
1479 MAIL FROM addresses; you will have to flip it by putting the
1483 sender_unqualified_hosts = localhost
1486 <p>in the main section of the exim configuration file. Note that
1487 this will result in such messages having an incorrect domain name
1488 attached to their return address (your SMTP listener's hostname
1489 rather than that of the remote mail server).</p>
1491 <h2><a id="T4" name="T4">T4. How can I use fetchmail with
1494 <p>Smail 3.2 is very nearly plug-compatible with sendmail, and may
1495 work fine out of the box.</p>
1497 <p>We have one report that when processing multiple messages from a
1498 single fetchmail session, smail sometimes delivers them in an order
1499 other than received-date order. This can be annoying because it
1500 scrambles conversational threads. This is not fetchmail's problem,
1501 it is an smail 'feature' and has been reported to the maintainers
1504 <p>Very recent smail versions require an
1505 <code>-smtp_hello_verify</code> option in the smail config file.
1506 This overrides smail's check to see that the HELO address is
1507 actually that of the client machine, which is never going to be the
1508 case when fetchmail is in the picture. According to RFC1123 an SMTP
1509 listener <em>must</em> allow this mismatch, so smail's new behavior
1510 (introduced sometime between 3.2.0.90 and 3.2.0.95) is a bug.</p>
1512 <p>You may also need to say
1513 <code>-smtp_hello_broken_allow=127.0.0.1</code> in order for smail
1514 to accept the "localhost" that fetchmail normally appends to
1515 recipient addresses.</p>
1517 <h2><a id="T5" name="T5">T5. How can I use fetchmail with SCO's
1520 <p>MMDF itself is difficult to configure, but it turns out that
1521 connecting fetchmail to MMDF's SMTP channel isn't that hard. You
1523 href="http://aplawrence.com/Unixart/uucptofetch.html">MMDF
1524 recipe</a> that describes replacing a UUCP link with fetchmail
1527 <h2><a id="T6" name="T6">T6. How can I use fetchmail with Lotus
1530 <p>The Lotus Notes SMTP gateway tries to deduce when it should
1531 convert \n to \r\n, but its rules are not the intuitive and
1532 correct-for-RFC822 ones. Use 'forcecr'.</p>
1534 <h2><a id="T7" name="T7">T7. How can I use fetchmail with Courier
1537 <p>The courier mta doesn't like RCPT addresses that look like
1538 <code>someone@localhost</code>. Work around this with an
1539 <code>smtphost</code> or <code>smtpaddress</code>.</p>
1541 <h2><a name="T8">T8. How can I use fetchmail with vbmailshield?</a></h2>
1543 <p>vbmailshield's SMTP interpreter is broken. It doesn't understand RSET.</p>
1545 <p>As a workaround, you can set batchlimit to 1 so RSET is never used.</p>
1548 <h1>How to make fetchmail work with various servers</h1>
1549 <h2><a id="S1" name="S1"><strike>S1. How can I use fetchmail with
1550 qpopper?</strike></a></h2>
1552 <p><em>The information that used to be here was obsolete and dropped.</em></p>
1554 <h2><a id="S2" name="S2">S2. How can I use fetchmail with Microsoft
1557 <p>It's been reliably reported that Exchange 2000's POP3 support is
1558 so broken that it's unusable. One symptom is that messages without
1559 a terminating newline get the POP3 message termination dot emitted
1560 -- you guessed it -- right after the last character of the message,
1561 with no terminating newline added. This will hang fetchmail or any
1562 other RFC-compliant server. IMAP is alleged to work OK, though.</p>
1564 <p>Older versions of Exchange are semi-usable. They randomly drop
1565 attachments on the floor, though. Microsoft acknowledges this
1566 as a known bug and apparently has no plans to fix it.</p>
1568 <p>Fetchmail using IMAP supports the proprietary NTLM mode used
1569 with M$ Exchange servers. To enable this, configure fetchmail with
1570 the --enable-NTLM option and recompile it. Specify a user option
1571 value that looks like 'user@domain': the part to the left of the @
1572 will be passed as the username and the part to the right as the
1575 <p>M$ Exchange violates the POP3 and IMAP RFCs. Its LIST command
1576 does not reveal the real sizes of mail in the pop mailbox, but the
1577 sizes of the compressed versions in the exchange mail database
1578 (thanks to Arjan De Vet and Guido Van Rooij for alerting us to this
1581 <p>Fetchmail works with M$ Exchange, despite this brain damage. Two
1582 features are compromised. One is that the --limit option will not
1583 work right (it will check against compressed and not actual sizes).
1584 The other is that a too-small SIZE argument may be passed to your
1585 ESMTP listener, assuming you're using one (this should not be a
1586 problem unless the actual size of the message is above the
1587 listener's configured length limit).</p>
1589 <p>Somewhat belatedly, I've learned that there's supposed to be a
1590 registry bit that can fix this breakage:</p>
1593 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1594 System\Pop3 Compatibility
1597 <p>This is a bitmask that controls the variations from the standard
1598 protocol. The bits defined are:</p>
1601 <dt>0x00000001:</dt>
1603 <dd>Report exact message sizes for the LIST command</dd>
1605 <dt>0x00000002:</dt>
1607 <dd>Allow arbitrary linear whitespace between commands and
1610 <dt>0x00000004:</dt>
1612 <dd>Enable the LAST command</dd>
1614 <dt>0x00000008:</dt>
1616 <dd>Allow an empty PASS command (needed for users with blank
1617 passwords, but illegal in the protocol)</dd>
1619 <dt>0x00000010:</dt>
1621 <dd>Relax the length restrictions for arguments to commands
1622 (protocol requires 40, but some user names may be longer than
1625 <dt>0x00000020:</dt>
1627 <dd>Allow spaces in the argument to the USER command.</dd>
1630 <p>There's another one that may be useful to know about:</p>
1633 KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1634 System\Pop3 Performance
1638 <dt>0x00000001:</dt>
1640 <dd>Render messages to a temporary stream instead of sending
1641 directly from the database (should always be on)</dd>
1643 <dt>0x00000002: Flag unrenderable messages (instead of just failing
1644 commands) (should only be on if you are seeing the problems
1645 reported in KB Q168109)</dt>
1647 <dt>0x00000004:</dt>
1649 <dd>Return from the QUIT command before all messages have been
1653 <p>The Microsoft pod-person who revealed this information to me
1654 admitted that he couldn't find it anywhere in their public
1657 <p>Another specific problem we have seen with Exchange servers has
1658 as its symptom a response to LOGIN that says "NO Ambiguous Alias".
1659 Grant Edwards writes:</p>
1661 <p>This means that Exchange Server is too f*&#ing stupid to
1662 figure out which mailbox belongs to you. Instead of actually
1663 keeping track of which inbox belongs to which user, it uses some
1664 half-witted, guess-o-matic heuristic to try to guess your mailbox
1665 name from your username.</p>
1667 <p>In your case it doesn't work because your username maps to more
1668 than one mailbox. For some people it doesn't work because their
1669 username maps to zero mailboxes. This is yet another inept, lame,
1670 almost criminally negligent design decision from our friends in
1673 <p>You've got several options:</p>
1676 <li>Get your administrator to configure the server so that
1677 usernames and mailbox names are the same.</li>
1679 <li>Get your administrator to add an alias that maps your username
1680 explicitly to your mailbox name.</li>
1683 <p>But, the best option involves finding a server that runs better
1686 <h2><a id="S3" name="S3">S3. How can I use fetchmail with HP
1689 <p>No special configuration is required, but OpenMail versions
1690 prior to 6.0 have an annoying bug similar to the big one in <a
1691 href="#S2">Microsoft Exchange</a>. The message sizes it gives in
1692 the LIST are rounded to the nearest 1024 bytes. It also has a nasty
1693 habit of discarding headers it doesn't recognize, such as X- and
1694 Resent- headers.</p>
1696 <p>As with M$ Exchange, the only real fix for these problems is to
1697 get a POP (or preferably IMAP) server that isn't brain-dead.
1698 OpenMail's project manager claims these bugs have been fixed in
1701 <p>We've had a more recent report (December 2001) that the TOP
1702 command fails, returning only one line regardless of its argument,
1703 on something identifying itself as "OpenMail POP3 interface".</p>
1705 <h2><a id="S4" name="S4">S4. How can I use fetchmail with Novell GroupWise?</a></h2>
1707 <p>The Novell GroupWise IMAP server would be better named
1708 GroupFoolish; it is (according to the designer of IMAP) unusably
1709 broken. Among other things, it doesn't include a required content
1710 length in its BODY[TEXT] response.</p>
1712 <p>Fetchmail works around this problem, but we strongly recommend
1713 voting with your dollars for a server that isn't brain-dead.</p>
1715 <h2><a id="S5" name="S5">S5. How can I use fetchmail with
1716 InterChange?</a></h2>
1718 <p>You can't. At least not if you want to be able to see
1719 attachments. InterChange has a bug similar to the MailMax server (<a
1720 href="#S6">see below</a>):
1721 it reports the message length with attachments but doesn't download
1722 them on TOP or RETR.</p>
1724 <p>On Jan 9 2001, the people at InfiniteMail sent me mail informing
1725 me that their new 3.61.08 release of InterChange fixes this
1726 problem. I don't have any reports one way or the other yet.</p>
1728 <h2><a id="S6" name="S6">S6. How can I use fetchmail with MailMax?</a></h2>
1730 <p>You can't. At least not if you want to be able to see
1731 attachments. MailMax has a bug; it reports the message length with
1732 attachments but doesn't download them on TOP or RETR.</p>
1734 <p>Also, we're told that TOP sometimes fails to retrieve the entire
1735 message even when enough lines have been specified. The MailMax
1736 developers have acknowledged this bug as of 4 May 2000, but there
1737 is no fix yet. If you must use this server, force RETR with the
1738 <tt>fetchall</tt> option.</p>
1740 <h2><a id="S7" name="S7">S7. How can I use fetchmail with FTGate?</a></h2>
1742 <p>The FTGate V2 server (and possibly older versions as well) has a
1743 weird bug. It answers OK twice to a TOP request! Use the
1744 <code>fetchall</code> option to force use of RETR and work around
1748 <h1>How to fetchmail work with specific ISPs</h1>
1749 <h2><a id="I1" name="I1">I1. How can I use fetchmail with CompuServe RPA?</a></h2>
1751 <p>First, make sure your fetchmail has the RPA support compiled in.
1752 Stock fetchmail binaries (such as you might get from an RPM) don't.
1753 You can check this by looking at the output of <code>fetchmail
1754 -V</code>; if you see the string "+RPA" after the version ID you're
1755 good to go, otherwise you'll have to build your own from sources
1756 (see the INSTALL file in the source distribution for
1759 <p>Give your CompuServe pass-phrase in lower case as your password.
1760 Add '@compuserve.com' to your user ID so that it looks like 'user
1761 <UserID>@compuserve.com', where <UserID> can be either
1762 your numerical userID or your E-mail nickname. An RPA-enabled
1763 fetchmail will automatically check for csi.com in the POP server's
1764 greeting line. If that's found, and your user ID ends with
1765 '@compuserve.com', it will query the server to see if it is
1766 RPA-capable, and if so do an RPA transaction rather than a
1767 plain-text password handshake.</p>
1769 <p><strong>Warning:</strong> the debug (-v -v) output of fetchmail
1770 will show your pass-phrase in Unicode!</p>
1772 <p>These two .fetchmailrc entries show the difference between an
1773 RPA and non-RPA configuration:</p>
1776 # This version will use RPA
1777 poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1778 user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
1779 is LOCAL_USER here options fetchall stripcr
1781 # This version will not use RPA
1782 poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1783 user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
1784 is LOCAL_USER here options fetchall stripcr
1787 <h2><a id="I2" name="I2">I2. How can I use fetchmail with Demon
1788 Internet's SDPS?</a></h2>
1790 <h3>Single-drop mode</h3>
1792 <p>You can get fetchmail to download the email for just one user
1793 from Demon Internet's POP3 server by giving it a username
1794 consisting of your Demon user name followed by your account name,
1795 with an at-sign between them.</p>
1797 <p>For example, to download email for the user
1798 <philh@vision25.demon.co.uk>, you could use the following
1799 .fetchmailrc file:</p>
1802 set postmaster "philh"
1803 poll pop3.demon.co.uk with protocol POP3:
1804 user "philh@vision25" is philh
1807 <h3>Multi-drop mode</h3>
1809 <p>Demon Internet's SDPS service is an implementation of POP3. All
1810 messages have a Received: header added when they enter the
1811 maildrop, like this:</p>
1814 Received: from punt-1.mail.demon.net by mailstore for fred@xyz.demon.co.uk
1815 id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
1818 <p>To enable multi-drop mode you need to tell fetchmail that
1819 'mailstore' is the name of the host which accepted the mail, and
1820 let it know the hostname part(s) of your E-mail address. The
1821 following example assumes that your hostname is xyz.demon.co.uk,
1822 and that you have also bought "mail forwarding" for the domain
1823 my-company.co.uk (in which case your MTA must also be configured to
1824 accept mail sent to user@my-company.co.uk)</p>
1827 poll pop3.demon.co.uk proto pop3 aka mailstore no dns:
1828 localdomains xyz.demon.co.uk my-company.co.uk
1832 <p>Note that Demon may delete mail on the server which is more than
1833 30 days old; see their <a
1834 href="http://www.demon.net/helpdesk/producthelp/mail/sdps-tech.html/">POP3
1835 page</a> for details.</p>
1837 <h3>The SDPS extension</h3>
1839 <p>There's a different way to do multidrop. It's not necessary on
1840 Demon Internet, since fetchmail can parse Received addresses, but
1841 the person who implemented this didn't know that. It may be useful
1842 if Demon Internet ever changes mail transports.</p>
1844 <p>SDPS includes a non-standard extension for retrieving the
1845 envelope of a message (*ENV), which fetchmail optionally supports
1846 if compiled with the --enable-SDPS option. If you have it, the
1847 first line of the fetchmail -V response will include the string
1850 <p>Once you have SDPS compiled in, fetchmail in POP3 mode will
1851 automatically detect when it's talking to a Demon Internet host in
1852 multidrop mode, and use the *ENV extension to get an envelope To
1855 <p>The autodetection works by looking at the hostname in the POP3
1856 greeting line; if you're accessing Demon Internet through a proxy
1857 it may fail. To force SDPS mode, pick "sdps" as your protocol.</p>
1859 <h2><a id="I3" name="I3">I3. How can I use fetchmail with usa.net's
1862 <p>Enable '<code>fetchall</code>'. A user reports that the 2.2
1863 version of USA.NET's POP server reports that you must use the
1864 '<code>fetchall</code>' option to make sure that all of the mail is
1865 retrieved, otherwise some may be left on the server. This is almost
1866 certainly a server bug.</p>
1868 <p>The usa.net servers (at least in their 2.2 version, June 1998)
1869 don't handle the TOP command properly, either. Regardless of the
1870 argument you give it, they retrieve only about 10 lines of the
1871 message. Fetchmail normally uses TOP for message retrieval in order
1872 to avoid marking messages seen, but '<code>fetchall</code>' forces
1873 it to use RETR instead.</p>
1875 <p>Also, we're told USA.NET adds a ton of hops to your messages.
1876 You may need to raise the MaxHopCount parameter in your sendmail.cf
1877 to avoid having fetched mail rejected.</p>
1879 <h2><a id="I4" name="I4">I4. How can I use fetchmail with geocities
1880 POP3 servers?</a></h2>
1882 <p>Nathan Cutler reports that the the mail.geocities.com POP3
1883 servers fail to include the first Received line of the message in
1884 the send to fetchmail. This can solve problems if your MUA
1885 interprets Received continuations as body lines and doesn't parse
1886 any of the following headers.</p>
1888 <p>Workaround is to use "mda" keyword or "--mda" switch:</p>
1891 mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
1894 <p>Replace \t with exactly one tabulation character.</p>
1896 <p>You should also consider using "fetchall" option because
1897 Geocities' servers sometimes think that the first 45 messages have
1898 already been read.</p>
1900 <h2><a id="I5" name="I5">I5. How can I use fetchmail with Hotmail or Lycos Webmail?</a></h2>
1902 <p>You can't directly. But you can use fetchmail with hotmail or lycos
1903 webmail with the help of the <a
1904 href='http://people.freenet.de/courierdave/'>HotWayDaemon</a>
1905 daemon. You don't even need to install hotwayd as a daemon in
1906 <samp>inetd.conf</samp> but can use it as a plugin. Your
1907 configuration should look like this:</p>
1910 poll localhost protocol pop3 tracepolls
1911 plugin "/usr/local/sbin/hotwayd -l 0 -p yourproxy:yourproxyport"
1912 username "youremail@hotmail.com" password "yourpassword"
1916 <p>As a second option you may consider using <a
1917 href="http://linux.cudeso.be/linuxdoc/gotmail.php">gotmail</a>.</p>
1919 <h2><a id="I6" name="I6">I6. How can I use fetchmail with MSN?</a></h2>
1921 <p>You can't. MSN uses something that looks like POP3, except the
1922 authentication part is nonstandard. And of course they don't
1923 document it, so nobody but their Windows clients can speak it.</p>
1925 <p>This is a customer lock-in tactic; we recommend boycotting MSN
1926 as the only appropriate response.</p>
1928 <p>As of 5.0.8, we have support for the client side of NTLM
1929 authentication. It's possible this may enable fetchmail to talk to
1930 MSN; if so, somebody should report it so this FAQ can be
1933 <h2><a id="I7" name="I7">I7. How can I use fetchmail with SpryNet?</a></h2>
1935 <p>The SpryNet POP3 servers mark a message queried with TOP as
1936 seen. This means that if your connection drops in mid-message, it
1937 may end up invisibly stuck on your mail spool. Use the
1938 <code>fetchall</code> flag to ensure that it's recovered on the
1941 <h2><a id="I8" name="I8">I8. How can I use fetchmail with comcast.net or
1942 other Maillennium servers?</a></h2>
1944 <p>Stock fetchmail will work with a
1945 Maillennium POP3/PROXY server... <em>but</em> this server will
1946 truncate "TOP" responses after 64 - 82 kB (we have varying reports),
1947 in violation of Internet Standard #53 aka. RFC-1939 (POP3). Don't
1948 mistake this for a fetchmail bug. (Reported July 2003.) Comcast
1949 documented they haven't understood what this is about in <a
1950 href="http://lists.ccil.org/pipermail/fetchmail-friends/2004-April/008523.html">two
1951 messages from April 2004.</a></p>
1953 <p>Beginning with version 6.3.2, fetchmail will fall back to the RETR
1954 command if the greeting string contains "Maillennium POP3/PROXY server",
1955 and print a warning message. This means however that fetchmail has no
1956 means to prevent the "seen" flag from being set on the server (Note that
1957 officially, POP3 has no notion of seen tracking, but it works for some
1960 <p>Workaround for older versions: use the <tt>fetchall</tt> option.</p>
1962 <h2><a id="I9" name="I9">I9. How can I use fetchmail with GMail/Google Mail?</a></h2>
1964 <p>Google's IMAP servers, as of April 2008, are broken and re-encode
1965 MIME-encoded headers improperly and are not feature-complete yet. The
1966 model how their servers organize mail also deviates in significant ways
1967 from what the POP3 or IMAP protocol 'fathers' conceived. This means all
1968 sorts of strange effects, for instance, your sent mail may show up in
1969 the mail that fetchmail fetches. It's best to avoid fetching mail from
1970 Google until they are using standards-compliant software.</p>
1973 <h1>How to set up well-known security and authentication
1975 <h2><a id="K1" name="K1">K1. How can I use fetchmail with SOCKS?</a></h2>
1977 <p>Giuseppe Guerini added a <kbd>--with-socks</kbd> compile-time option
1978 that supports linking with socks library. If you specify the value of
1979 this option as "yes", the configure script will try to find the Rconnect
1980 library and set the makefile up to link it. You can also specify a
1981 directory containing the Rconnect library.</p>
1983 <p>Alan Schmitt has added a similar <kbd>--with-socks5</kbd> option that may
1984 work better if you have a recent version of the SOCKS library.</p>
1986 <p>In either case, fetchmail has no direct configuration hooks, but you
1987 can specify which socks configuration file the library should read by
1988 means of the <tt>SOCKS_CONF</tt> environment variable. In order to
1989 bypass the SOCKS proxy altogether, you could run (adding your usual
1990 options to the end of this line):</p>
1992 <pre>env SOCKS_CONF=/dev/null fetchmail</pre>
1994 <h2><a id="K2" name="K2">K2. How can I use fetchmail with IPv6 and
1997 <p>To use fetchmail with IPv6, you need a system that supports
1998 IPv6, the "Basic Socket Interface Extensions for IPv6" (RFC 2133).
2001 <p>The NRL IPv6+IPsec software distribution can be obtained from:
2003 href="http://web.mit.edu/network/isakmp/">http://web.mit.edu/network/isakmp/</a></p>
2005 <p>More information on using IPv6 with Linux can be obtained
2010 href="http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html">
2011 http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html</a></li>
2014 <h2><a id="K3" name="K3">K3. How can I get fetchmail to work with
2017 <p>Use the <tt>plugin</tt> option. This is dead simple with
2021 plugin "ssh %h /usr/sbin/imapd"
2024 <p>You may have to use a different absolute pathname, whatever the
2025 location of imapd on your mailserver is. This option tells
2026 fetchmail that instead of opening a connection on the server's port
2027 143 and doing standard IMAP authentication, fetchmail should ssh to
2028 the server and run imapd, using the more secure ssh authentication
2029 (as well as getting ssh's end-to-end encryption). Most IMAP daemons
2030 will detect that they've been called from the command line and
2031 assume the connection is preauthenticated.</p>
2033 <p>POP3 daemons aren't quite as smart. They won't know they are
2034 preauthenticated in this mode, so you'll actually have to ship your
2035 password. It will be under ssh encryption, though, so that
2036 shouldn't be a problem.</p>
2038 <h2><a id="K4" name="K4">K4. What do I have to do to use the
2039 IMAP-GSS protocol?</a></h2>
2041 <p>Fetchmail can use RFC1731 GSSAPI authorization to safely
2042 identify you to your IMAP server, as long as you can share
2043 Kerberos V credentials with your mail host and you have a GSSAPI-capable
2044 IMAP server - those are few.</p>
2046 <p>fetchmail does not compile in support for GSS by
2047 default, since it requires libraries from the Kerberos V
2048 distribution (available via FTP at <a
2049 href="ftp://athena-dist.mit.edu/pub/ATHENA/kerberos">athena-dist.mit.edu</a>).
2050 If you have these, compiling in GSS support is simple: add a
2051 <code>--with-gssapi=[/path/to/krb5/root]</code> option to
2052 configure. For instance, I have all of my Kerberos V libraries
2053 installed under /usr/krb5 so I run <code>configure
2054 --with-gssapi=/usr/krb5</code></p>
2056 <p>Setting up Kerberos V authentication is beyond the scope of this
2057 FAQ (you may find Jim Rome's paper <a
2058 href="http://www.ornl.gov/~jar/HowToKerb.html">How to Kerberize
2059 your site</a> helpful), but you'll at least need to add a
2060 credential for imap/[mailhost] to the keytab of the mail server
2061 (IMAP doesn't just use the host key). Then you'll need to have your
2062 credentials ready on your machine (cf. kinit).</p>
2064 <p>After that things are very simple. Set your protocol to imap-gss
2065 in your .fetchmailrc, and omit the password, since imap-gss doesn't
2066 need one. You can specify a username if you want, but this is only
2067 useful if your mailbox belongs to a username different from your
2068 Kerberos principal.</p>
2070 <p>Now you don't have to worry about your password appearing in
2071 cleartext in your .fetchmailrc, or across the network.</p>
2073 <h2><a id="K5" name="K5">K5. How can I use fetchmail with
2076 <p>You'll need to have the <a
2077 href="http://www.openssl.org/">OpenSSL</a> libraries installed, and they
2078 should at least be version 0.9.6.
2079 Configure with --with-ssl. If you have the OpenSSL libraries
2080 installed in commonly-used default locations, this will
2081 suffice. If you have them installed in a non-default location,
2082 you'll need to specify the OpenSSL installation directory as an argument
2083 to --with-ssl after an equal sign.</p>
2085 <p>Fetchmail binaries built this way support <code>ssl</code>,
2086 <code>sslkey</code>, and <code>sslcert</code> options that control
2087 SSL encryption, and will automatically use <code>tls</code> if the
2088 server offers it. You will need to have an SSL-enabled mailserver to
2089 use these options. See the manual page for details and some words
2090 of care on the limited security provided.</p>
2092 <p>If your open OpenSSL session dies with a message that complains
2093 "PRNG not seeded", update or improve your operating system. This
2094 means that the OpenSSL library on your machine has been unable to
2095 locate a source of random bits from which to seed its random-number
2096 generator; normally these come from the <tt>/dev/urandom</tt>, and
2097 this message probably means your OS doesn't have that device.</p>
2099 <p>An interactive program could seed the random number generator
2100 from keystroke timings or some other form of user input. Because
2101 fetchmail is primarily designed to run forever as a background
2102 daemon, that option is not available in this case.</p>
2104 <p>If you don't have the libraries installed, but do have the
2105 OpenSSL utility toolkit, something like this may work (but will not
2106 authenticate the server):</p>
2109 poll MYSERVER port 993 plugin "openssl s_client -connect %h:%p"
2110 protocol imap username MYUSERNAME password MYPASSWORD
2113 <p>You should note that SSL is only secure against a "man-in-the-middle"
2114 attack if the client is able to verify that the peer's public key is the
2115 correct one, and has not been substituted by an attacker. fetchmail can do
2116 this in one of two ways: by verifying the SSL certificate, or by checking
2117 the fingerprint of the peer's public key.</p>
2119 <p>There are three parts to SSL certificate verification: checking that the
2120 domain name in the certificate matches the hostname you asked to connect to;
2121 checking that the certificate expiry date has not passed; and checking that
2122 the certificate has been signed by a known Certificate Authority (CA). This
2123 last step takes some preparation, as you need to install the root
2124 certificates of all the CA's which you might come across.</p>
2126 <p>The easiest way to do this is using the root CA keys supplied in the
2127 OpenSSL distribution, which means you need to download and unpack the
2128 source tarball from www.openssl.org. Once you have done that:</p>
2131 <li><code>mkdir /etc/ssl/certs</code></li>
2132 <li>in the openssl-x.x.x/certs directory: <code>cp *.pem /etc/ssl/certs/</code></li>
2133 <li>in the openssl-x.x.x/tools directory: edit c_rehash and set
2134 <code>$dir="/etc/ssl"</code></li>
2135 <li>run "perl c_rehash". This generates a number of symlinks within the
2136 /etc/ssl/certs/ directory</li>
2139 <p>Now in .fetchmailrc, set option sslcertpath to point to this
2143 poll pop3.example.com proto pop3 uidl no dns
2144 user foobar@example.com password xyzzy is foobar ssl sslcertpath /etc/ssl/certs
2147 <p>If the server certificate has not been signed by a known CA (e.g. it is a
2148 self-signed certificate), then this certificate validation will always
2151 <p>Certificate verification is always attempted. If it fails, by default a
2152 warning is printed but the connection carries on (which means you are not
2153 protected against attack). If your server's certificate has been properly
2154 set up and verifies correctly, then add the "sslcertck" option to enforce
2155 validation. If your server doesn't have a valid certificate though (e.g. it
2156 has a self-signed certificate) then it will never verify, and the only way
2157 you can protect yourself is by checking the fingerprint.</p>
2159 <p>To check the peer fingerprint: first use fetchmail -v once to connect to
2160 the host, at a time when you are pretty sure that there is no attack in
2161 progress (e.g. you are not traversing any untrusted network to reach the
2162 server). Make a note of the fingerprint shown. Now embed this in your
2163 .fetchmailrc using the sslfingerprint option: e.g.</p>
2166 poll pop3.example.com proto pop3 uidl no dns
2167 user foobar@example.com password xyzzy is foobar
2168 ssl sslfingerprint "67:3E:02:94:D3:5B:C3:16:86:71:37:01:B1:3B:BC:E2"
2171 <p>When you next connect, the public key presented by the server will be
2172 verified against the fingerprint given. If it's different, it may mean that
2173 a man-in-the-middle attack is in progress - or it might just mean that the
2174 server changed its key. It's up to you to determine which has happened.</p>
2176 <h2><a id="K6" name="K6">K6. How can I tell fetchmail not to use TLS
2177 if the server advertises it? Why does fetchmail use SSL even
2178 though not configured?</a></h2>
2180 <p>Some servers advertise STLS (POP3) or STARTTLS (IMAP), and fetchmail
2181 will automatically attempt TLS negotiation if SSL was enabled at compile
2182 time. This can however cause problems if the upstream didn't configure
2183 his certificates properly.</p>
2185 <p>In order to prevent fetchmail from trying TLS (STLS, STARTTLS)
2186 negotiation, add this option:</p>
2188 <pre>sslproto ssl23</pre>
2190 <p>This restricts fetchmail's SSL/TLS protocol choice from the default
2191 "SSLv2, SSLv3, TLSv1" to the two SSL variants, disabling TLSv1. Note
2192 however that this causes the connection to be unencrypted unless an
2193 encrypting "plugin" is used or SSL is requested explicitly.</p>
2196 <h1>Runtime fatal errors</h1>
2197 <h2><a id="R1" name="R1">R1. Fetchmail isn't working, and -v shows
2198 'SMTP connect failed' messages.</a></h2>
2200 <p>Fetchmail itself is probably working, but your SMTP port 25
2201 listener is down or inaccessible.</p>
2203 <p>The first thing to check is if you can telnet to port 25 on your
2204 smtp host (which is normally 'localhost' unless you've specified an
2205 smtp option in your .fetchmailrc or on the command line) and get a
2206 greeting line from the listener. If the SMTP host is inaccessible
2207 or the listener is down, fix that first.</p>
2209 <p>In Red Hat Linux 6.x, SMTP is disabled by default. To fix this,
2210 set "DAEMON=yes" in your /etc/sysconfig/sendmail file, then restart
2211 sendmail by running "/sbin/service sendmail restart".</p>
2213 <p>If the listener seems to be up when you test with telnet, the
2214 most benign and typical problem is that the listener had a
2215 momentary seizure due to resource exhaustion while fetchmail was
2216 polling it -- process table full or some other problem that stopped
2217 the listener process from forking. If your SMTP host is not
2218 'localhost' or something else in /etc/hosts, the fetchmail glitch
2219 could also have been caused by transient nameserver failure.</p>
2221 <p>Try running fetchmail -v again; if it succeeds, you had one of
2222 these kinds of transient glitch. You can ignore these hiccups,
2223 because a future fetchmail run will get the mail through.</p>
2225 <p>If the listener tests up, but you have chronic failures trying
2226 to connect to it anyway, your problem is more serious. One way to
2227 work around chronic SMTP connect problems is to use --mda. But this
2228 only attacks the symptom; you may have a DNS or TCP routing
2229 problem. You should really try to figure out what's going on
2230 underneath before it bites you some other way.</p>
2232 <p>We have one report (from toby@eskimo.com) that you can sometimes
2233 solve such problems by doing an <code>smtp</code> declaration with
2234 an IP address that your routing table maps to something other than
2235 the loopback device (he used ppp0).</p>
2237 <p>We also have a report that this error can be caused by having an
2238 /etc/hosts file that associates your client host name with more
2239 than one IP address.</p>
2241 <p>It's also possible that your DNS configuration isn't looking at
2242 <code>/etc/hosts</code> at all. If you're using libc5, look at
2243 <code>/etc/resolv.conf</code>; it should say something like:</p>
2249 <p>so your <code>/etc/hosts</code> file is checked first. If you're
2250 running GNU libc6, check your <code>/etc/nsswitch.conf</code> file.
2251 Make sure it says something like</p>
2257 <p>again, in order to make sure <code>/etc/hosts</code> is seen
2260 <p>If you have a hostname set for your machine, and this hostname
2261 does not appear in /etc/hosts, you will be able to telnet to port
2262 25 and even send a mail with rcpt to: user@host-not-in-/etc/hosts,
2263 but fetchmail can't seem to get in touch with sendmail, no matter
2264 what you set smtpaddress to.</p>
2266 <p>We had another report from a Linux user of fetchmail 2.1 who
2267 solved his SMTP connection problem by removing the reference to
2268 -lresolv from his link line and relinking. Apparently in some older
2269 Linux distributions the libc bind library version works better.</p>
2271 <p>As of 2.2, the configure script has been hacked so the bind
2272 library is linked only if it is actually needed. So under Linux it
2273 won't be, and this particular cause should go away.</p>
2275 <h2><a id="R2" name="R2">R2. When I try to configure an MDA,
2276 fetchmail doesn't work.</a></h2>
2278 <p>(I hear this one from people who have run into the blank-line
2279 problem in <a href="#X1">X1</a>.)</p>
2281 <p>Try sending yourself test mail and retrieving it using the
2282 command-line options '<code>-k -m cat</code>'. This will dump
2283 exactly what fetchmail retrieves to standard output (plus the
2284 Received line fetchmail itself adds to the headers).</p>
2286 <p>If the dump doesn't match what shows up in your mailbox when you
2287 configure an MDA, your MDA is mangling the message. If it doesn't
2288 match what you sent, then fetchmail or something on the server is
2291 <h2><a id="R3" name="R3">R3. Fetchmail dumps core when given an
2292 invalid rc file.</a></h2>
2294 <p>Note that this bug should no longer occur when using prepackaged
2295 fetchmail versions or installing unmodified original tarballs, since
2296 these ship with a proper parser .c file.</p>
2298 <p>This is usually reported from AIX or Ultrix, but has even been
2299 known to happen on Linuxes without a recent version of
2300 <code>flex</code> installed. The problem appears to be a result of
2301 building with an archaic version of lex.</p>
2303 <p>Workaround: fix the syntax of your .fetchmailrc file.</p>
2305 <p>Fix: build and install the latest version of <a
2306 href="http://flex.sourceforge.net/">flex</a>.</p>
2308 <h2><a id="R4" name="R4"><strike>R4. Fetchmail dumps core in -V mode, but
2309 operates normally otherwise.</strike></a></h2>
2311 <p><em>The information that used to be here referred to bugs in Linux libc5
2312 systems, which are deemed obsolete by now.</em></p>
2314 <h2><a id="R5" name="R5">R5. Running fetchmail in daemon mode
2315 doesn't work.</a><br/>
2318 <p>We have one report from a SunOS 4.1.4 user that trying to run
2319 fetchmail in detached daemon mode doesn't work, but that using the
2320 same options with -N (nodetach) is OK. We have another report of
2321 similar behavior from one Linux user, but many other Linux users
2322 report no problem.</p>
2324 <p>If this happens, you have a specific portability problem with
2325 the code in daemon.c that detaches and backgrounds the daemon
2326 fetchmail. The isolated Linux case has been chased down to a
2327 failure in dup(2) that may reflect a glibc bug.</p>
2329 <p>As a workaround, you can start fetchmail with -N and an
2330 ampersand to background it. A Sun user recommends this:</p>
2333 (fetchmail --nodetach <other params> &)
2336 <p>The extra pair of parens is significant --- it makes sure that
2337 the process detaches from the initial shell (one more shell is
2338 started and dies immediately, detaching fetchmail and making it
2339 child of PID 1). This is important when you start fetchmail
2340 interactively and than quit interactive shell. The line above makes
2341 sure fetchmail lives after that!</p>
2343 <h2><a id="R6" name="R6">R6. Fetchmail randomly dies with socket
2346 <p>Check the MTU value in your PPP interface reported by
2347 <code>/sbin/ifconfig</code>. If it's over 600, change it in your
2348 PPP options file. (<code>/etc/ppp/options</code> on my box). Here
2349 are option values that work:</p>
2356 <p>Another circumstance that can trigger this is if you are polling
2357 a virtual-mail-server name that is round-robin connected to
2358 different actual servers, so you get different IP addresses on
2359 different poll cycles. To work around this, change the poll name
2360 either to the real name of one of the servers in the ring or to a
2361 corresponding IP address.</p>
2363 <h2><a id="R7" name="R7">R7. Fetchmail running as root stopped
2364 working after an OS upgrade</a></h2>
2366 <p>In RH 6.0, the HOME value in the boot-time root environment
2367 changed from /root to / as the result of a change in init. Move
2368 your .fetchmailrc or use a -f option to explicitly point at the
2369 file. (Oddly, a similar problem has been reported from Debian
2372 <h2><a id="R8" name="R8">R8. Fetchmail is timing out after fetching
2373 certain messages but before deleting them</a></h2>
2375 <p>There's a TCP/IP stalling problem under Redhat 6.0 (and possibly
2376 other recent Linuxes) that can cause this symptom. Brian Boutel
2380 <p>TCP timestamps are turned on on my Linux boxes (I assume it's
2381 now the default). This uses 12 extra bytes per segment. When the
2382 tcp connection starts, the other end agrees a MSS of 1460, and then
2383 fragments 1460 byte chunks into 1448 and 12, because is is not
2384 allowing for the timestamp.</p>
2386 <p>Then, for reasons I can't explain, it waits a long time
2387 (typically 2 minutes) after the ack is sent before sending the next
2388 (fragmented) packet. Turning off tcp timestamps avoids the
2389 fragmentation and restores normal behaviour. To do this,
2392 <p>echo 0 > /proc/sys/net/ipv4/tcp_timestamps</p>
2394 <p>I'm still unclear about the details of why this is happening. At
2395 least [now] I am now getting good performance and no queue
2399 <h2><a id="R9" name="R9">R9. Fetchmail is timing out during message
2402 <p>This is probably a general networking issue. Sending a "RETR"
2403 command will cause the server to start sending large amounts of
2404 data, which means large packets. If your networking layer has a
2405 packet-fragmentation problem or improper firewall settings break Path
2406 MTU discovery (when for instance all ICMP traffic is blocked), that's
2407 where you'll see it.</p>
2409 <h2><a id="R10" name="R10"><strike>R10. Fetchmail is dying with
2410 SIGPIPE.</strike></a></h2>
2412 <p><em>Fetchmail 6.3.5 and newer block SIGPIPE, and many older versions have
2413 already handled this signal, so you shouldn't be seeing SIGPIPE
2416 <h2><a id="R11" name="R11">R11. My server is hanging or emitting
2417 errors on CAPA.</a></h2>
2419 <p>Your POP3 server is broken. You can work around this with the
2420 declaration <tt>auth password</tt> in your .fetchmailrc.</p>
2422 <h2><a id="R12" name="R12">R12. Fetchmail isn't working and reports
2423 getaddrinfo errors.</a></h2>
2424 <ol><li>Make sure you haven't mistyped the host name or address, and that
2425 your DNS is working. If you cannot fix DNS, give the numeric host
2426 literal, for instance, 192.168.0.1</li>
2427 <li>Make sure your <code>/etc/services</code> file (or other
2428 services database) contains the necessary service entries. If you
2429 cannot fix the services database, use the --service option and give the
2430 numeric port address. Common port addresses are:<table
2431 summary="Common port addresses for IMAP, POP3 and their SSL
2433 <tr><th>service</th><th>port</th></tr>
2434 <tr><td>IMAP</td><td>143</td></tr>
2435 <tr><td>IMAP+SSL</td><td>993</td></tr>
2436 <tr><td>POP3</td><td>110</td></tr>
2437 <tr><td>POP3+SSL</td><td>995</td></tr>
2440 <h2><a id="R13" name="R13">R13. What does "Interrupted system call"
2443 <p>Non-fatal signals (such as timers set by fetchmail itself) can
2444 interrupt long-running functions and will then be reported as
2445 "Interrupted system call". These can sometimes be timeouts.</p>
2448 <h1>Hangs and lockups</h1>
2449 <h2><a id="H1" name="H1">H1. Fetchmail hangs when used with
2452 <p>Your problem may be with pppd's 'demand' option. We have a
2453 report that fetchmail doesn't play well with it, but works with
2454 pppd if 'demand' is turned off. We have no idea why this is.</p>
2456 <h2><a id="H2" name="H2">H2. Fetchmail hangs during the MAIL FROM
2459 <p>The symptom: 'fetchmail -v' retrieves mail fine, but appears to
2460 hang after sending the MAIL FROM command</p>
2463 SMTP> MAIL FROM: <someone@somewhere>
2466 <p>The hang is actually occuring when sendmail looks up a sender's
2467 address in DNS. The problem isn't in fetchmail but in the
2468 configuration of sendmail. You must enable the 'nodns' and
2469 'nocanonify' features of sendmail.</p>
2471 <p>Here was my fix for RedHat 7.2:</p>
2474 <li># cd /etc/mail</li>
2476 <li># cp sendmail.mc sendmail-mine.mc</li>
2478 <li>Edit sendmail-mine.mc and add lines:
2486 <li>Build a new sendmail.cf
2489 # m4 sendmail-mine.cf > /etc/sendmail.cf
2493 <li>Restart sendmail.</li>
2496 <p>For more details consult the file
2497 /usr/share/sendmail-cf/README.</p>
2499 <h2><a id="H3" name="H3">H3. Fetchmail hangs while fetching
2502 <p>The symption: 'fetchmail -v' retrieves the first few messages,
2503 but hangs returning:</p>
2506 fetchmail: SMTP< 550 5.0.0 Access denied
2507 fetchmail: SMTP> RSET
2508 fetchmail: SMTP< 250 2.0.0 Reset state
2509 .......fetchmail: flushed
2510 fetchmail: POP3> DELE 1
2511 fetchmail: POP3< +OK marked deleted
2514 <p>Check and see if you're allowing sendmail connections through
2517 <p>Adding 'sendmail : 127.0.0.1' to /etc/hosts.allow could solve
2521 <h1>Disappearing mail</h1>
2522 <h2><a id="D1" name="D1">D1. I think I've set up fetchmail
2523 correctly, but I'm not getting any mail.</a></h2>
2525 <p>Maybe you have a .forward or alias set up that you've forgotten
2526 about. You should probably remove it.</p>
2528 <p>Or maybe you're trying to run fetchmail in multidrop mode as
2529 root without a .fetchmailrc file. This doesn't do what you think it
2530 should; see question <a href="#C1">C1</a>.</p>
2532 <p>Or you may not be connecting to the SMTP listener. Run fetchmail
2533 -v and see <a href="#R1">R1</a>.</p>
2535 <p>Or you may have your local user set incorrectly. In the
2539 user 'remoteuser' there with password '*' is 'localuser' here
2542 <p>make sure that 'localuser' does exist and can receive mail.</p>
2544 <h2><a id="D2" name="D2">D2. All my mail seems to disappear after a
2545 dropped connection.</a></h2>
2547 <p>One POP3 daemon used in the Berkeley Unix world that reports
2548 itself as POP3 version 1.004 actually throws the queue away. 1.005
2549 fixed that. If you're running this one, upgrade immediately. (It
2550 also truncates long lines at column 1024.)</p>
2552 <p>Many POP servers, if an interruption occurs, will restore the
2553 whole mail queue after about 10 minutes. Better ones will restore it
2554 right away. If you have an interruption and don't see it right
2555 away, cross your fingers and wait ten minutes before retrying.</p>
2557 <p>Good servers are designed to restore the entire queue, including
2558 messages you have deleted. If you have one of these and it flakes out on
2559 you a lot, try setting a small <code>--fetchlimit</code> value. This
2560 will result in more IP connects to the server, but will mean it actually
2561 executes changes to the queue more often.</p>
2563 <h2><a id="D3" name="D3">D3. Mail that was being fetched when I
2564 interrupted my fetchmail seems to have been vanished.</a></h2>
2566 <p>Fetchmail only sends a delete mail request to the server when
2567 either (a) it gets a positive delivery acknowledgment from the SMTP
2568 listener, or (b) it gets one of the spam-filter errors (see the
2569 description of the <code>antispam></code> option) from the
2570 listener. No interrupt can cause it to lose mail.</p>
2572 <p>However, IMAP2bis has a design problem in that its normal fetch
2573 command marks a message 'seen' as soon as the fetch command to get
2574 it is sent down. If for some reason the message isn't actually
2575 delivered (you take a line hit during the download, or your port 25
2576 listener can't find enough free disk space, or you interrupt the
2577 delivery in mid-message) that 'seen' message can lurk invisibly in
2578 your server mailbox forever.</p>
2580 <p>Workaround: add the '<code>fetchall</code>' keyword to your
2583 <p>Solution: switch to an <a href="http://www.imap.org/">IMAP4</a>
2587 <h1>Multidrop-mode problems</h1>
2588 <h2><a id="M1" name="M1">M1. I've declared local names, but all my
2589 multidrop mail is going to root anyway.</a></h2>
2591 <p>Somehow your fetchmail is never recognizing the hostname part of
2592 recipient names it parses out of Envelope-header lines (or these are
2593 improperly configured) as
2594 matching a name within the designated domains. To check this, run
2595 fetchmail in foreground with -v -v on. You will probably see a lot
2596 of messages with the format "line rejected, %s is not an alias of
2597 the mailserver" or "no address matches; forwarding to %s."</p>
2599 <p>These errors usually indicate some kind of configuration
2602 <p>The easiest workaround is to add a '<code>via</code>' option (if
2603 necessary) and add enough '<code>aka</code>' declarations to cover all
2604 of your mailserver's aliases, then say '<code>no dns</code>'. This will
2605 take DNS out of the picture (though it means mail may be uncollected if
2606 it's sent to an alias of the mailserver that you don't have listed).</p>
2608 <p>Occasionally these errors indicate the sort of header-parsing
2609 problem described in <a href="#M7">M7</a>.</p>
2611 <h2><a id="M2" name="M2">M2. I can't seem to get fetchmail to route
2612 to a local domain properly.</a></h2>
2614 <p>A lot of people want to use fetchmail as a poor man's
2615 internetwork mail gateway, picking up mail accumulated for a whole
2616 domain in a single server mailbox and then routing based on what's
2617 in the To/Cc/Bcc lines.</p>
2619 <p>In general, this is not really a good idea. It would be smarter
2620 to just let the mail sit in the mailserver's queue and use
2621 fetchmail's ETRN or ODMR modes to trigger SMTP sends periodically
2622 (of course, this means you have to poll more frequently than the
2623 mailserver's expiration period). If you can't arrange this, try
2624 setting up a UUCP feed.</p>
2626 <p>If neither of these alternatives is available, multidrop mode
2627 may do (though you <em>are</em> going to get hurt by some mailing
2628 list software; see the caveats under THE USE AND ABUSE OF MULTIDROP
2629 MAILBOXES on the man page, and check what is needed at <a
2630 href="http://home.pages.de/~mandree/mail/multidrop">Matthias
2631 Andree's "Requisites for working multidrop
2632 mailboxes"</a>). If you want to try it, the way to do it is
2633 with the '<code>localdomains</code>' option.</p>
2635 <p>In general, if you use localdomains you need to make sure of two
2638 <p><strong>1. You've actually set up your .fetchmailrc entry to
2639 invoke multidrop mode.</strong></p>
2641 <p>Many people set a '<code>localdomains</code>' list and then
2642 forget that fetchmail wants to see more than one name (or the
2643 wildcard '*') in a '<code>here</code>' list before it will do
2644 multidrop routing.</p>
2646 <p><strong>2. You may have to set 'no envelope'.</strong></p>
2648 <p>Normally, multidrop mode tries to deduce an envelope address
2649 from a message before parsing the To/Cc/Bcc lines (this enables it
2650 to avoid losing to mailing list software that doesn't put a
2651 recipient address in the To lines).</p>
2653 <p>Some ways of accumulating a whole domain's messages in a single
2654 server mailbox mean it all ends up with a single envelope address
2655 that is useless for rerouting purposes. In this particular case, sell
2656 your ISP a clue. If that does not work, you may have to set
2657 '<code>no envelope</code>' to prevent fetchmail from being
2658 bamboozled by this, but a missing envelope makes multidrop routing
2661 <p>Check also answer <a href="#T1">T1</a> on a reliable way to do
2662 multidrop delivery if your ISP (or your mail redirection provider)
2665 <h2><a id="M3" name="M3">M3. I tried to run a mailing list using
2666 multidrop, and I have a mail loop!</a></h2>
2668 <p>This isn't fetchmail's fault. Check your mailing list. If the
2669 list expansion includes yourself or anybody else at your mailserver
2670 (that is, not on the client side) you've created a mail loop. Just
2671 chop the host part off any local addresses in the list.</p>
2673 <p>If you use sendmail, you can check the list expansion with
2674 <code>sendmail -bv</code>.</p>
2676 <h2><a id="M4" name="M4"><strike>M4. My multidrop fetchmail seems to be
2677 having DNS problems.</strike></a></h2>
2679 <p><em>The answer that used to be here no longer applies to
2682 <h2><a id="M5" name="M5">M5. I'm seeing long DNS delays before each
2683 message is processed.</a></h2>
2685 <p>Use the '<code>aka</code>' option to pre-declare as many of your
2686 mailserver's DNS names as you can. When an address's host part
2687 matches an aka name, no DNS lookup needs to be done to check
2690 <p>If you're sure you've pre-declared all of your mailserver's DNS
2691 names, you can use the '<code>no dns</code>' option to prevent
2692 other hostname parts from being looked up at all.</p>
2694 <p>Sometimes delays are unavoidable. Some SMTP listeners try to
2695 call DNS on the From-address hostname as a way of checking that the
2696 address is valid.</p>
2698 <h2><a id="M6" name="M6">M6. How do I get multidrop mode to work
2699 with majordomo?</a></h2>
2701 <p>In order for sendmail to execute the command strings in the
2702 majordomo alias file, it is necessary for sendmail to think that
2703 the mail it receives via SMTP really is destined for a local user
2704 name. A normal virtual-domain setup results in delivery to the
2705 default mailbox, rather than expansion through majordomo.</p>
2707 <p>Michael <michael@bizsystems.com> gave us a recipe for
2708 dealing with this case that pairs a run control file like this:</p>
2711 poll your.pop3.server proto pop3:
2713 localdomains virtual.localdomain1.com virtual.localdomain2.com ...
2714 user yourISPusername is root * here,
2715 password yourISPpassword fetchall
2718 <p>with a hack on your local sendmail.cf like this:</p>
2721 #############################################
2722 # virtual info, local hack for ruleset 98 #
2723 #############################################
2725 # domains to treat as direct mapped local domain
2727 CVvirtual.localdomain1.com virtual.localdomain2.com ...
2728 ---------------------------
2730 -------------------------
2731 # handle virtual users
2733 R$+ <@ $=V . > $: $1 < @ $j . >
2734 R< @ > $+ < @ $=V . > $: $1 < @ $j . >
2735 R< @ > $+ $: $1
2736 R< error : $- $+ > $* $#error $@ $1 $: $2
2737 R< $+ > $+ < @ $+ > $: $>97 $1
2740 <p>This ruleset just strips virtual domain names off the addresses
2741 of incoming mail. Your sendmail must be 8.8 or newer for this to
2742 work. Michael says:</p>
2744 <blockquote>I use this scheme with 2 virtual domains and the
2745 default ISP user+domain and service about 30 mail accounts +
2746 majordomo on my inside pop3 server with fetchmail and sendmail
2749 <h2><a id="M7" name="M7">M7. Multidrop mode isn't parsing envelope
2750 addresses from my Received headers as it should.</a></h2>
2752 <p>It may happen that you're getting what appear to be well-formed
2753 sendmail Received headers, but fetchmail can't seem to extract an
2754 envelope address from them. There can be a couple of reasons for
2757 <h3>Spurious Received lines need to be skipped:</h3>
2759 <p>First, fetchmail might be looking at the wrong Received header.
2760 Normally it looks only on the first one it sees, on the theory that
2761 that one was last added and is going to be the one containing your
2762 mailserver's theory of who the message was addressed to.</p>
2764 <p>Some (unusual) mailserver configurations will generate extra
2765 Received lines which you need to skip. To arrange this, use the
2766 optional skip prefix argument of the 'envelope' option; you may
2767 need to say something like '<code>envelope 1 Received</code>' or
2768 '<code>envelope 2 Received</code>'.</p>
2770 <h3>The 'by' clause doesn't contain a mailserver alias:</h3>
2772 <p>When fetchmail parses a Received line that looks like</p>
2775 Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
2776 by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
2777 for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
2780 <p>it checks to see if 'iserv.ttns.net' is a DNS alias of your
2781 mailserver before accepting 'ksturgeon@fbceg.org' as an envelope
2782 address. This check might fail if your DNS were misconfigured, or
2783 if you were using 'no dns' and had failed to declare iserv.ttns.net
2784 as an alias of your server.</p>
2786 <h2><a id="M8" name="M8">M8. Users are getting multiple copies of
2789 <p>It's a consequence of multidrop. What's happening is that you
2790 have N users subscribed to the same list. The list software sends N
2791 copies, not knowing they will end up in the same multidrop box.
2792 Since they are both locally addressed to all N users, fetchmail
2793 delivers N copies to each user.</p>
2795 <p>Fetchmail tries to eliminate adjacent duplicate messages in a
2796 multidrop mailbox. However, this logic depends on the message-ID
2797 being identical in both copies. It also depends on the two copies
2798 being adjacent in the server mailbox. The former is usually the
2799 case, but the latter condition sometimes fails in a
2800 timing-dependent way if the server was processing multiple incoming
2803 <p>I could eliminate this problem by keeping a list of all
2804 message-IDs received during a poll so far and dropping any message
2805 that matches a seen mail ID. The trouble is that this is an O(N**2)
2806 operation that might significantly slow down the retrieval of large
2809 <p>The real solution however is to make sure that fetchmail can find the
2810 envelope recipient properly, which will reliably prevent this message
2814 <h1>Mangled mail</h1>
2815 <h2><a id="X1" name="X1">X1. Spurious blank lines are appearing in
2816 the headers of fetched mail.</a></h2>
2818 <p>What's probably happening is that the POP/IMAP daemon on your
2819 mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
2820 something in your delivery path (most likely an old version of the
2821 <em>deliver</em> program, which sendmail often calls to do local
2822 delivery) is failing to recognize it as a header.</p>
2824 <p>This is not fetchmail's problem. The first thing to try is
2825 installing a current version of <em>deliver</em>. If this doesn't
2826 work, try to figure out which other program in your mail path is
2827 inserting the blank line and replace that. If you can't do either
2828 of these things, pick a different MDA (such as maildrop) and
2829 declare it with the '<code>mda</code>' option.</p>
2831 <h2><a id="X2" name="X2">X2. My mail client can't see a Subject
2834 <p>First, see <a href="#X1">X1</a>. This is quite probably the same
2835 problem (X-POP3-Rcpt header or something similar being inserted by
2836 the server and choked on by an old version of
2837 <em>deliver</em>).</p>
2839 <p>The O'Reilly sendmail book does warn that IDA sendmail doesn't
2840 process X- headers correctly. If this is your problem, all I can
2841 suggest is replacing IDA sendmail, because it's broken and not
2842 RFC822 conformant.</p>
2844 <h2><a id="X3" name="X3">X3. Messages containing "From" at the start of
2845 line are being split.</a></h2>
2847 <p>If you know the messages aren't split in your server mailbox,
2848 then this is a problem with your POP/IMAP server, your client-side
2849 SMTP listener or your local delivery agent. Fetchmail cannot split
2852 <p>Some POP server daemons ignore Content-Length headers and split
2853 messages on From lines. We have one report that the 2.1 version of
2854 the BSD popper program (as distributed on Solaris 2.5 and
2855 elsewhere) is broken this way.</p>
2857 <p>You can test this. Declare an mda of 'cat' and send yourself one
2858 piece of mail containing "From" at start of a line. If you see a
2859 split message, your POP/IMAP server is at fault. Upgrade to a more
2862 <p>Sendmail and other SMTP listeners don't split RFC822 messages
2863 either. What's probably happening is either sendmail's local
2864 delivery agent or your mail reader are not quite RFC822-conformant
2865 and are breaking messages on what it thinks are Unix-style From
2866 headers. You can figure out which by looking at your client-side
2867 mailbox with vi or more. If the message is already split in your
2868 mailbox, your local delivery agent is the problem. If it's not,
2869 your mailreader is the problem.</p>
2871 <p>If you can't replace the offending program, take a look at your
2872 sendmail.cf file. There will likely be a line something like</p>
2875 Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
2878 <p>describing your local delivery agent. Try inserting the 'E'
2879 option in the flags part (the F= string). This will make sendmail
2880 turn each dangerous start-of-line From into a >From, preventing
2881 programs further downstream from acting up.</p>
2883 <h2><a id="X4" name="X4">X4.</a> <a id="generic_mangling"
2884 name="generic_mangling">My mail is being mangled in a new and
2885 different way</a></h2>
2887 <p>The first thing you need to do is pin down what program is doing
2888 the mangling. We don't like getting bug reports about fetchmail
2889 that are actually due to some other program's malfeasance, so
2890 please go through this diagnostic sequence before sending us a
2893 <p>There are five possible culprits to consider, listed here in the
2894 order they pass your mail:</p>
2897 <li>Programs upstream of your server mailbox.</li>
2899 <li>The POP or IMAP server on your mailserver host.</li>
2901 <li>The fetchmail program itself.</li>
2903 <li>Your local sendmail.</li>
2905 <li>Your LDA (local delivery agent), as called by sendmail or
2906 specified by <code>mda</code>.</li>
2909 <p>Often it happens that fetchmail itself is OK, but using it
2910 exposes pre-existing bugs in your downstream software, or your
2911 downstream software has a bad interaction with POP/IMAP. You need
2912 to pin down exactly where the message is being garbled in order to
2913 deduce what is actually going on.</p>
2915 <p>The first thing to do is send yourself a test message, and
2916 retrieve it with a .fetchmailrc entry containing the following (or
2917 by running with the equivalent command-line options):</p>
2920 mda "cat >MBOX" keep fetchall
2923 <p>This will capture what fetchmail gets from the server, except
2924 for (a) the extra Received header line fetchmail prepends, (b)
2925 header address changes due to <code>rewrite</code>, and (c) any
2926 end-of-line changes due to the <code>forcecr</code> and
2927 <code>stripcr</code> options. MBOX will in fact contain what
2928 programs downstream of fetchmail see.</p>
2930 <p>The most common causes of mangling are bugs and
2931 misconfigurations in those downstream programs. If MBOX looks
2932 unmangled, you will know that is what is going on and that it is
2933 not fetchmail's problem. Take a look at the other FAQ items in this
2934 section for possible clues about how to fix your problem.</p>
2936 <p>If MBOX looks mangled, the next thing to do is compare it with
2937 your actual server mailbox (if possible). That's why you specified
2938 <code>keep</code>, so the server copy would not be deleted. If your
2939 server mailbox looks mangled, programs upstream of your server
2940 mailbox are at fault. Unfortunately there is probably little you
2941 can do about this aside from complaining to your site postmaster,
2942 and nothing at all fetchmail can do about it!</p>
2944 <p>More likely you'll find that the server copy looks OK. In that
2945 case either the POP/IMAP server or fetchmail is doing the mangling.
2946 To determine which, you'll need to telnet to the server port and
2947 simulate a fetchmail session yourself. This is not actually hard
2948 (both POP3 and IMAP are simple, text-only, line-oriented protocols)
2949 but requires some attention to detail. You should be able to use a
2950 fetchmail -v log as a model for a session, but remember that the
2951 "*" in your LOGIN or PASS command dump has to be replaced with your
2952 actual password.</p>
2954 <p>The objective of manually simulating fetchmail is so you can see
2955 exactly what fetchmail sees. If you see a mangled message, then
2956 your server is at fault, and you probably need to complain to your
2957 mailserver administrators. However, we like to know what the broken
2958 servers are so we can warn people away from them. So please send us
2959 a transcript of the session including the mangling <em>and the
2960 server's initial greeting line</em>. Please tell us anything else
2961 you think might be useful about the server, like the server host's
2962 operating system.</p>
2964 <p>If your manual fetchmail simulation shows an unmangled message,
2965 congratulations. You've found an actual fetchmail bug, which is a
2966 pretty rare thing these days. Complain to us and we'll fix it.
2967 Please include the session transcript of your manual fetchmail
2968 simulation along with the other things described in the FAQ entry
2969 on <a href="#G3">reporting bugs</a>.</p>
2971 <h2><a id="X5" name="X5"><strike>X5. Using POP3, retrievals seems to be
2972 fetching too much!</strike></a></h2>
2974 <p><em>The information that used to be here pertained to fetchmail 4.4.7 or
2975 older, which should not be used. Use a recent fetchmail version.</em></p>
2977 <h2><a id="X6" name="X6">X6. My mail attachments are being dropped
2978 or mangled.</a></h2>
2980 <p>Fetchmail doesn't discard attachments; fetchmail doesn't have any idea
2981 that attachments are there. Fetchmail treats the body of each message as
2982 an uninterpreted byte stream and passes it through without alteration.
2983 If you are not receiving attachments through fetchmail, it is because
2984 your mailserver is not sending them to you.</p>
2986 <p>The fix for this is to replace your mailserver with one that works.
2987 If its operating system makes this difficult, you should replace its
2988 operating system with one that works. Windows- and NT-based POP servers
2989 seem especially prone to mangle attachments. If you are running one
2990 of these, replacing your server with a Unix machine is probably the
2991 only effective solution.</p>
2993 <p>We've had sporadic reports of problems with Microsoft Exchange and
2994 Outlook servers. These sometimes randomly fail to ship
2995 attachments to your client. This is a known bug, acknowledged by
2998 <p>They may also mangle the attachments they do pass through. If you
2999 see unreadable attachments with a ContentType of "application/x-tnef",
3000 you're having this problem. The <a
3001 href="http://world.std.com/~damned/software.html">TNEF</a> utility may
3004 <p>The Mail Max POP3 server and the InterChange and Imail IMAP
3005 servers are known to simply drop MIME attachments when uploading
3008 <p>We've also had a report that Lotus Notes sometimes trashes the
3009 MIME type of messages. In particular, it seems to modify MIME
3010 headers of type application/pdf, mangling the type to
3011 application/octet-stream. It may corrupt other MIME types as
3014 <p>The IMAP service of Lotus Domino has a known bug in the way it
3015 generates MIME Content-type headers (observed on Lotus Domino
3016 5.0.2b). It's a subtle one that doesn't show up when Netscape
3017 Messenger and other clients use a FETCH BODY[] to grab the whole
3018 message. When fetchmail uses FETCH RFC822.HEADER and FETCH
3019 RFC822.TEXT to get first the header and then the body, Domino
3020 generates different Boundary tags for each part, e.g. one tag is
3021 declared in the Content-type header and another is used to separate
3022 the MIME parts in the body. This doesn't work. (I have heard a
3023 rumor that this bug is scheduled to be fixed in Domino release 6;
3024 you can find a workaround at contrib/domino.)</p>
3026 <p>Rob Funk explains: Unfortunately there also remain many mail
3027 user agents that don't write correct MIME messages. One big
3028 offender is Sun MailTool attachments, which are formatted enough
3029 like MIME that some programs could get confused; these are
3030 generated by the mailtool and dtmail programs (the mail programs in
3031 Sun's OpenWindows and CDE environments).</p>
3033 <p>One solution to problems related to misformatted MIME
3034 attachments is the <a
3035 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/">emil</a>
3037 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/TUTORIAL.html">tutorial</a>
3038 file at that site for details on emil. It is useful for converting
3039 character sets, attachment encodings, and attachment formats. At
3040 this writing, emil does not appear to have been maintained since a
3041 patch to version 2.1.0beta9 in late 1997, but it is still
3044 <p>One good way of using emil is from within procmail. You can have
3045 procmail look for signs of problematic message formatting, and pipe
3046 those messages through emil to be fixed. emil will not always be
3047 able to fix the problem, in which case the message is
3050 <p>A possible rule to be inserted into a .procmailrc file for using
3055 * 1^1 ^Content-Type: \/X-sun[^;]*
3056 * 1^1 ^Content-Type: \/application/mac-binhex[^;]*
3057 * 1^1 ^Content-Transfer-Encoding: \/x-binhex[^;]*
3058 * 1^1 ^Content-Transfer-Encoding: \/x-uuencode[^;]*
3060 LOG="Converting $MATCH
3063 | emil -A B -T Q -B BA -C iso-8859-1 -H Q -F MIME \
3064 | gawk '{gsub(/\r\n?/,"\n");print $0}'
3068 <p>The "1^1" in the conditions is a way of specifying to procmail
3069 that if any one of the four listed expressions is found in the
3070 message, the total condition is considered true, and the message
3071 gets passed into emil. These four subconditions check whether the
3072 message has a Sun attachment, a binhex attachment, or a uuencoded
3073 attachment; there are others that could be added to check these
3074 things better and to check other relevant conditions. The "LOG="
3075 line writes a line into the procmail log; the lone double-quote
3076 beginning the following line makes sure the log entry gets an
3077 end-of-line character. The call to gawk (GNU awk) is for fixing
3078 end-of-line conventions, since emil sometimes leaves those in the
3079 format of the originating machine; it could probably be replaced
3080 with a sed subsitution.</p>
3082 <p>The emil call itself tries to ensure that the message uses:</p>
3085 <li>BinHex encoding for any Apple Macintosh-only attachments</li>
3087 <li>Quoted-Printable encoding for text (when necessary)</li>
3089 <li>Base64 Encoding for binary attachments</li>
3091 <li>iso-8859-1 character set for text (unfortunately emil can't yet
3092 convert from windows-1252 to iso-8859-1)</li>
3094 <li>Quoted-Printable encoding for headers</li>
3096 <li>MIME attachment format</li>
3099 <p>Most of these (the primary exceptions being the character set
3100 and the Apple binary format) are as they should be for good
3101 internet interoperability.</p>
3103 <p>Some mail servers (Lotus Domino is a suspect here) mangle
3104 Sun-formatted messages, so the conversion to MIME needs to happen
3105 before such programs see the message. The ideal is to rid the world
3106 of Sun-formatted messages: don't use mailtool for sending
3107 attachments (it doesn't understand MIME anyway, and most of the
3108 world doesn't understand its attachments, so it really shouldn't be
3109 used at all), and make sure dtmail is set to use MIME rather than
3110 mailtool's format.</p>
3112 <h2><a id="X7" name="X7">X7. Some mail attachments are hanging
3115 <p>This isn't fetchmail's problem either; fetchmail doesn't know
3116 anything about mail attachments and doesn't treat them any
3117 differently from plain message data.</p>
3119 <p>The most usual cause of this problem seems to be bugs in your
3120 network transport layer's capability to handle the very large
3121 TCP/IP packets that attachments tend to turn into. You can test
3122 this theory by trying to download the offending message through a
3123 webmail account; using HTTP for the message tends to simulate
3124 large-packet stress rather well, and you will probably find that
3125 the messages that seem to be choking fetchmail will make your HTTP
3126 download speed drop to zero.</p>
3128 <p>This problem can be caused by subtle bugs in the
3129 packet-reassembly layer of your TCP/IP stack; these often don't
3130 manifest at normal packet sizes. It may also be caused by
3131 malfunctioning path-MTU discovery on the mailserver. Or, if there's
3132 a modem in the link, it may be because the attachment contains the
3133 Hayes mode escape "+++".</p>
3135 <h2><a id="X8" name="X8">X8. A spurious ) is being appended to my
3138 <p>Blame it on that rancid pile of dung and offal called Microsoft
3139 Exchange. Due to the problem described in <a href="#S2">S2</a>, the
3140 IMAP support in fetchmail cannot follow the IMAP protocol 100%.
3141 Most of the time it doesn't matter, but if you combine it with an
3142 SMTP server that behaves unusually, you'll get a spurious ) at
3145 <p>One piece of software that can trigger this is the Interchange
3146 mail server, as used by, e.g., mailandnews.com. Here's what
3149 <p>1. Someone sends mail to your account. The last line of the
3150 message contains text. So at the SMTP level, the message ends with,
3151 e.g. "blahblah\r\n.\r\n"</p>
3153 <p>2. The SMTP handler sees the final "\r\n.\r\n" and recognizes
3154 the end of the message. However, instead of doing the normal thing,
3155 which is tossing out the ".\r\n" and leaving the first '\r\n' as
3156 part of the email body, Interchange throws out the whole
3157 "\r\n.\r\n", and leaves the email body without any line terminator
3158 at the end of it. RFC821 does not forbid this, though it probably
3161 <p>3. Fetchmail, or some other IMAP client, asks for the message.
3162 IMAP returns it, but it's enclosed inside parentheses, according to
3163 the protocol. The message size in bytes is also present. Because
3164 the message doesn't end with a line terminator, the IMAP client
3172 <p>where the ')' is from IMAP.</p>
3174 <p>4. Fetchmail only deals with complete lines, and can't trust the
3175 stated message size because Microsoft Exchange fscks it up.</p>
3177 <p>5. As a result, fetchmail takes the final 'blahblah)' and puts
3178 it at the end of the message it forwards on. If you have verbosity
3179 on, you'll get a message about actual != expected.</p>
3181 <p>There is no fix for this. The nuke mentioned in <a
3182 href="#S2">S2</a> looks more tempting all the time.</p>
3184 <h2><a id="X9" name="X9">X9. Missing "Content-Transfer-Encoding" header
3185 with Domino IMAP</a></h2>
3187 <p>Domino 6 IMAP was found by Anthony Kim in February 2006 to
3188 erroneously omit the "Content-Transfer-Encoding" header in messages
3189 downloaded through IMAP, causing messages to display improperly. This
3190 happened with Domino's incoming mail format configured to "Prefers
3191 MIME". Solution: switch Domino to "Keep in Sender's format".</p>
3194 href="http://lists.ccil.org/pipermail/fetchmail-friends/2006-March/010015.html">Anthony
3199 <h1>Other problems</h1>
3200 <h2><a id="O1" name="O1">O1. The --logfile option doesn't work if
3201 the logfile doesn't exist.</a></h2>
3203 <p>This is a feature, not a bug. It's in line with normal practice
3204 for system daemons and allows you to suppress logging by removing
3205 the log file, without hacking potentially fragile startup scripts.
3206 To get around it, just touch(1) the logfile before you run fetchmail
3207 (this will have no effect on the contents of the logfile if it already
3210 <h2><a id="O2" name="O2">O2. Every time I get a POP or IMAP message,
3211 the header is dumped to all my terminal sessions.</a></h2>
3213 <p>Fetchmail uses the local sendmail to perform final delivery,
3214 which Mozilla and other clients don't do; the announcement of
3215 new messages is done by a daemon that sendmail pokes. There should
3216 be a "biff" command to control this. Type</p>
3222 <p>to turn it off. If this doesn't work, try the command</p>
3228 <p>which is essentially what <code>biff -n</code> will do. If this
3229 doesn't work, comment out any reference to "comsat" in your
3230 /etc/inetd.conf file and reload (or restart) inetd.</p>
3232 <p>In Slackware Linux distributions, the last line in /etc/profile
3245 to solve the problem system-wide.
3247 <h2><a id="O3" name="O3">O3. Does fetchmail reread its rc file
3248 every poll cycle?</a></h2>
3250 <p>No, but versions 5.2.2 and later will notice when you modify
3251 your rc file and restart, reading it. Note that this causes troubles if
3252 you need to provide a password via the console, unless you're running in
3253 --nodetach mode.</p>
3255 <h2><a id="O4" name="O4">O4. Why do deleted messages show up again
3256 when I take a line hit while downloading?</a></h2>
3258 <p>According to the POP3 RFCs, deletes aren't actually performed
3259 until you issue the end-of-session QUIT command. Fetchmail cannot
3260 fix this, but there is a workaround: use the --expunge option with a
3261 reasonably low figure that works for you. Try 10 for a start.</p>
3263 <p>IMAP is less susceptible to this problem, because the "deleted"
3264 message marks are persistent, but they aren't in POP3. Note that the
3265 --expunge default for IMAP is different than the default for POP3.</p>
3267 <p>If you get very unlucky, you might take a line hit in the window
3268 between the delete and the expunge. If you've set a longer expunge
3269 interval, the window gets wider. This problem should correct itself
3270 the next time you complete a successful query.</p>
3272 <h2><a id="O5" name="O5">O5. Why is fetched mail being logged with
3273 my name, not the real From address?</a></h2>
3275 <p>Because logging is done based on the address indicated by the
3276 sending SMTP's MAIL FROM, and some listeners are picky about that
3279 <p>Some SMTP listeners get upset if you try to hand them a MAIL
3280 FROM address naming a different host than the originating site for
3281 your connection. This is a feature, not a bug -- it's supposed to
3282 help prevent people from forging mail with a bogus origin site.
3283 (RFC 1123 says you shouldn't do this exclusion...)</p>
3285 <p>Since the originating site of a fetchmail delivery connection is
3286 localhost, this effectively means these picky listeners will barf
3287 on any MAIL FROM address fetchmail hands them with an @ in it!</p>
3289 <p>Versions 2.1 and up try the header From address first and fall
3290 back to the calling-user ID. So if your SMTP listener isn't picky,
3291 the log will look right.</p>
3293 <h2><a id="O6" name="O6">O6. I'm seeing long sendmail delays or
3294 hangs near the start of each poll cycle.</a></h2>
3296 <p>Sendmail does a hostname lookup when it first starts up, and
3297 also each time it gets a HELO in listener mode.</p>
3299 <p>Your resolver configuration may be causing one of these lookups
3300 to fail and time out. Check your <code>/etc/resolv.conf</code>,
3301 <code>/etc/host.conf</code>, <code>/etc/nsswitch.conf</code> (if you
3302 have the latter two) and you <code>/etc/hosts</code> files. Make sure
3303 your hostname and fully-qualified domain name are both in
3304 <code>/etc/hosts</code>, and that hosts is looked at before DNS is
3305 queried. You probably also want your remote mail server(s) to be in the
3308 <p>You can suppress the startup-time lookup if need to by reconfiguring
3309 with <code>FEATURE(nodns)</code>.</p>
3311 <p>Configuring your bind library to cache DNS lookups locally may
3312 help, and is a good idea for speeding up other services as well.
3313 Switching to a faster MTA like <a
3314 href="http://www.postfix.org/">Postfix</a> might help.</p>
3316 <h2><a id="O7" name="O7">O7. Why doesn't fetchmail deliver mail in
3317 date-sorted order?</a></h2>
3319 <p>Because that's not the order the server hands it to fetchmail
3322 <p>Fetchmail getting mail from a POP server delivers mail in the
3323 order that your server delivers mail. Fetchmail can't do anything
3324 about this; it's a limitation of the underlying POP protocol.</p>
3326 <p>In theory it might be possible for fetchmail in IMAP mode to
3327 sort messages by date, but this would be in violation of two basics
3328 of fetchmail's design philosophy: (a) to be as simple and
3329 transparent a pipe as possible, and (b) to <em>hide</em>, rather
3330 than emphasize, the differences between the remote-fetch protocols
3333 <p>Re-ordering messages is a user-agent function, anyway.</p>
3335 <h2><a id="O8" name="O8">O8. I'm using pppd. Why isn't my monitor
3336 option working?</a></h2>
3338 <p>There is a combination of circumstances that can confuse
3339 fetchmail. If you have set up demand dialing with pppd, and pppd
3340 has an idle timeout, and you have lcp-echo-interval set, then the
3341 lcp-echo-interval time must be longer than the pppd idle timeout.
3342 Otherwise it is going keep increasing the packet counters that
3343 fetchmail relies upon, triggering fetchmail into polling after its
3344 own delay interval and thus preventing the pppd link from ever
3345 reaching its inactivity timeout.</p>
3347 <h2><a id="O9" name="O9">O9. Why does fetchmail keep retrieving the
3348 same messages over and over?</a></h2>
3350 <p>First, check to see that you haven't enabled the
3351 <cite>keep</cite> and <cite>fetchall</cite> option. If you have,
3352 turn one of them off - which one, depends on why they have been set in
3353 the first place, and to a lesser degree on the upstream server.</p>
3355 <p>This can also happen when some other mail client is logged in to
3356 your mail server, if it uses a simple exclusive-locking scheme (and
3357 many, especially most POP3 servers, do exactly that). Your
3358 fetchmail is able to retrieve the messages, but because the mailbox
3359 is write-locked by the other instance yours can neither mark
3360 messages seen or delete them. The solution is to either (a) wait
3361 for the other client to finish, or (b) terminate it.</p>
3363 <h2><a id="O10" name="O10"><strike>O10. Why is the received date on all my
3364 messages the same?</strike></a></h2>
3366 <p><em>The answer that used to be here made no sense and was dropped.</em></p>
3368 <h2><a name="O11">O11. I keep getting messages that say "Repoll
3369 immediately" in my logs.</a></h2>
3371 <p>This is your server barfing on the CAPA probe that fetchmail sends.
3372 Because some servers like to drop the connection after that probe,
3373 fetchmail will re-poll immediately with this probe defeated.</p>
3375 <p>If you run fetchmail in daemon mode (say "set daemon 600"), you will
3376 get the message only once per run.</p>
3378 <p>If you set an authentication method explicitly (say, with
3379 <code>auth password</code>), you will never get the message.</p>
3381 <h2><a name="O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a></h2>
3383 <p>This is a feature, not a bug.</p>
3385 <p>Any 4xx response (like 451) indicates a transient (temporary) error.
3386 This means that the mail could be accepted if retried later. Lookup
3387 failures are normally transient errors as a mail should not get
3388 rejected if a dns server is unreachable or down.</p>
3390 <p>A permanent reject response is of the form 5xx (like 550).</p>
3392 <p>You could tell your SMTP server to not lookup any addresses if you are
3393 not keen on checking the sender addresses. This problem typically
3394 occurs if your mail server is not checking the sender addresses, but
3395 your local server is.</p>
3397 <p>Or you could declare <code>antispam 451</code>, which is not
3398 recommended though, as it may cause mail loss.</p>
3400 <p>Or, you could check your nameserver configuration and query logs for
3403 <p>All these issues are not related to fetchmail directly.</p>
3405 <h2><a name="O13">O13. I want timestamp information in my fetchmail logs.</a></h2>
3407 <p>Write a <code>preconnect</code> command in your configuration file that
3408 does something like "date >> $HOME/fetchmail.log".</p>
3410 <h2><a name="O14">O14. Fetchmail no longer deletes oversized mails with
3413 <p>Use <code>--limitflush</code> (available since release 6.3.0) to
3414 delete oversized mails along with the <code>--limit</code> option. If
3415 you are already having <code>flush</code> in your rcfile to delete
3416 oversized mails, <em>replace</em> it with <code>limitflush</code> to
3417 avoid losing mails unintentionally.</p>
3419 <p>The <code>--flush</code> option is primarily designed to delete
3420 mails which have been read/downloaded but not deleted yet. This option
3421 cannot be overloaded to delete oversized mails as it cannot be guessed
3422 whether the user wants to delete only read/downloaded mails or only
3423 oversized mails or both when a user specifies both
3424 <code>--limit</code> and <code>--flush</code>. Hence, a separate
3425 <code>--limitflush</code> has been added to resolve the ambiguity.</p>
3427 <h2><a name="O15">O15. Fetchmail always retains the first message in the
3430 <p>This happens when fetchmail sees an "X-IMAP:" header in the very
3431 first message in your mailbox. This usually stems from a message like
3432 the one shown below, which is automatically created on your server. This
3433 message shows up if the University of Washington IMAP or PINE software
3434 is used on the server together with a POP2 or POP3 daemon that is not
3435 aware of these messages, such as some versions of Qualcomm Popper
3440 From MAILER-DAEMON Wed Nov 23 11:38:42 2005
3441 Date: 23 Nov 2005 11:38:42 +0100
3442 From: Mail System Internal Data <MAILER-DAEMON@imap.example.org>
3443 Subject: DON'T DELETE THIS MESSAGE -- FOLDER INTERNAL DATA
3444 Message-ID: <1132742322@imap.example.org>
3445 X-IMAP: 1132742306 0000000001
3448 This text is part of the internal format of your mail folder, and is not
3449 a real message. It is created automatically by the mail system software.
3450 If deleted, important folder data will be lost, and it will be re-created
3451 with the data reset to initial values.
3455 <p>As this message does not contain useful information, fetchmail is not
3456 retrieving it. And deleting it might slow down the server if you are
3457 keeping messages on the server, and the server would recreate it
3458 anyways, that's why fetchmail does not bother to delete it either.</p>
3460 <h2><a name="O16">O16. Why is the Fetchmail FAQ only available in
3461 ISO-216 A4 format? How do I get the FAQ in Letter format?</a></h2>
3463 <p>All the world uses ISO-216:1975 "A4" paper except for North America.
3464 Using A4 format reaches far more people than (formerly known as DIN A4,
3465 from DIN 476) format. Besides that, A4 paper <em>is</em> available in North
3467 For further information on the Letter-vs-A4 story, see:</p>
3468 <ul><li><a href="http://www.cl.cam.ac.uk/~mgk25/iso-paper.html">Markus
3469 Kuhn: "International standard paper sizes"</a></li>
3471 href="http://betweenborders.com/wordsmithing/a4-vs-us-letter/">Brian
3472 Forte: "A4 vs US Letter"</a></li></ul>
3474 <p>Offering the document formatted for two different paper sizes would
3475 bloat the package beyond reason, and formatting in a way that fits A4
3476 and Letter paper formats would be a waste of paper in most parts of the
3477 world. For that reason, fetchmail only ships with an A4 formatted PDF
3480 <p>To create a letter-sized PDF, install <a
3481 href="http://www.htmldoc.org/">HTMLDOC</a>, edit
3482 <code>fetchmail-FAQ.book</code> in the source directory with your
3483 favorite text editor, replace <samp>--size A4</samp> by <samp>--size
3484 letter</samp>, and type:
3487 make fetchmail-FAQ.pdf
3492 <table width="100%" cellpadding="0" summary="Canned page footer">
3494 <td width="30%">Back to <a href="index.html">Fetchmail Home
3496 <td width="30%" align="right">$Date$</td>
3501 <address>Eric S. Raymond <a
3502 href="mailto:esr@thyrsus.com"><esr@thyrsus.com></a><br />
3503 Matthias Andree</address>