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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>Before reporting any bug, please read <a href="#G3">G3</a> for
35 advice on how to include diagnostic information that will get your
36 bug fixed 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. 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 behave like Outlook Express.</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/>
154 <h2 id="C_K">How to set up well-known security and authentication
157 <a href="#K1">K1. How can I use fetchmail with SOCKS?</a><br/>
158 <a href="#K2">K2. How can I use fetchmail with IPv6 and IPsec?</a><br/>
159 <a href="#K3">K3. How can I get fetchmail to work with ssh?</a><br/>
160 <a href="#K4">K4. What do I have to do to use the IMAP-GSS protocol?</a><br/>
161 <a href="#K5">K5. How can I use fetchmail with SSL?</a><br/>
162 <a href="#K6">K6. How can I tell fetchmail not to try TLS if the server
163 advertises it? Why does fetchmail use SSL even though not configured?</a><br/>
165 <h2 id="C_R">Runtime fatal errors</h2>
167 <a href="#R1">R1. Fetchmail isn't working, and -v shows 'SMTP
168 connect failed' messages.</a><br/>
169 <a href="#R2">R2. When I try to configure an MDA, fetchmail doesn't
171 <a href="#R3">R3. Fetchmail dumps core when given an invalid rc
173 <a href="#R4"><strike>R4. Fetchmail dumps core in -V mode, but operates
174 normally otherwise.</strike></a><br/>
175 <a href="#R5">R5. Running fetchmail in daemon mode doesn't
177 <a href="#R6">R6. Fetchmail randomly dies with socket errors.</a><br/>
178 <a href="#R7">R7. Fetchmail running as root stopped working after
179 an OS upgrade</a><br/>
180 <a href="#R8">R8. Fetchmail is timing out after fetching certain
181 messages but before deleting them</a><br/>
182 <a href="#R9">R9. Fetchmail is timing out during message fetches</a><br/>
183 <a href="#R10"><strike>R10. Fetchmail is dying with SIGPIPE.</strike></a><br/>
184 <a href="#R11">R11. My server is hanging or emitting errors on CAPA.</a><br/>
185 <a href="#R12">R12. Fetchmail isn't working and reports getaddrinfo
187 <a href="#R13">R13. What does "Interrupted system call" mean?</a>
189 <h2 id="C_H">Hangs and lockups</h2>
191 <a href="#H1">H1. Fetchmail hangs when used with pppd.</a><br/>
192 <a href="#H2">H2. Fetchmail hangs during the MAIL FROM
194 <a href="#H3">H3. Fetchmail hangs while fetching mail.</a><br/>
197 <h2 id="C_D">Disappearing mail</h2>
199 <a href="#D1">D1. I think I've set up fetchmail correctly, but I'm
200 not getting any mail.</a><br/>
201 <a href="#D2">D2. All my mail seems to disappear after a dropped
203 <a href="#D3">D3. Mail that was being fetched when I interrupted my
204 fetchmail seems to have been vanished.</a><br/>
207 <h2 id="C_M">Multidrop-mode problems</h2>
209 <a href="#M1">M1. I've declared local names, but all my multidrop
210 mail is going to root anyway.</a><br/>
211 <a href="#M2">M2. I can't seem to get fetchmail to route to a local
212 domain properly.</a><br/>
213 <a href="#M3">M3. I tried to run a mailing list using multidrop,
214 and I have a mail loop!</a><br/>
215 <a href="#M4"><strike>M4. My multidrop fetchmail seems to be having DNS
216 problems.</strike></a><br/>
217 <a href="#M5">M5. I'm seeing long DNS delays before each message is
219 <a href="#M6">M6. How do I get multidrop mode to work with
221 <a href="#M7">M7. Multidrop mode isn't parsing envelope addresses
222 from my Received headers as it should.</a><br/>
223 <a href="#M8">M8. Users are getting multiple copies of
227 <h2 id="C_X">Mangled mail</h2>
229 <a href="#X1">X1. Spurious blank lines are appearing in the headers
230 of fetched mail.</a><br/>
231 <a href="#X2">X2. My mail client can't see a Subject
233 <a href="#X3">X3. Messages containing "From" at start of line are
234 being split.</a><br/>
235 <a href="#X4">X4. My mail is being mangled in a new and different
237 <a href="#X5"><strike>X5. Using POP3, retrievals seems to be fetching too
238 much!</strike></a><br/>
239 <a href="#X6">X6. My mail attachments are being dropped or
241 <a href="#X7">X7. Some mail attachments are hanging
243 <a href="#X8">X8. A spurious ) is being appended to my
245 <a href="#X9">X9. Missing "Content-Transfer-Encoding" header
246 with Domino IMAP</a><br/>
247 <h2 id="C_O">Other problems</h2>
249 <a href="#O1">O1. The --logfile option doesn't work if the logfile
250 doesn't exist.</a><br/>
251 <a href="#O2">O2. Every time I get a POP or IMAP message the header
252 is dumped to all my terminal sessions.</a><br/>
253 <a href="#O3">O3. Does fetchmail reread its rc file every poll
255 <a href="#O4">O4. Why do deleted messages show up again when I take
256 a line hit while downloading?</a><br/>
257 <a href="#O5">O5. Why is fetched mail being logged with my name,
258 not the real From address?</a><br/>
259 <a href="#O6">O6. I'm seeing long sendmail delays or hangs near the
260 start of each poll cycle.</a><br/>
261 <a href="#O7">O7. Why doesn't fetchmail deliver mail in date-sorted
263 <a href="#O8">O8. I'm using pppd. Why isn't my monitor option
265 <a href="#O9">O9. Why does fetchmail keep retrieving the same
266 messages over and over?</a><br/>
267 <a href="#O10"><strike>O10. Why is the received date on all my messages the
268 same?</strike></a><br/>
269 <a href="#O11">O11. I keep getting messages that say "Repoll
270 immediately" in my logs.</a><br/>
271 <a href="#O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a><br/>
272 <a href="#O13">O13. I want timestamp information in my fetchmail logs.</a><br/>
273 <a href="#O14">O14. Fetchmail no longer deletes oversized mails with
275 <a href="#O15">O15. Fetchmail always retains the first message in the
277 <a href="#O16">O16. Why is the Fetchmail FAQ only available in
278 ISO-216 A4 format? How do I get the FAQ in Letter
282 <h1 id="G">General problems</h1>
283 <h2><a id="G1" name="G1">G1. What is fetchmail and why should I
286 <p>Fetchmail is a one-stop solution to the remote mail retrieval
287 problem for Unix machines, quite useful to anyone with an
288 intermittent or dynamic-IP connection to a remote mailserver, SLIP or
289 PPP dialup, or leased line when SMTP isn't desired. Fetchmail can
290 collect mail using any variant of POP or IMAP and forwards to a the
291 local SMTP (via TCP socket) or LMTP (via TCP or Unix socket) listener or
292 into an MDA program, enabling all the normal
293 forwarding/filtering/aliasing mechanisms that would apply to local mail
294 or mail arriving via a full-time TCP/IP connection.</p>
296 <p>Fetchmail is not a toy or a coder's learning exercise, but an
297 industrial-strength tool capable of transparently handling every
298 retrieval demand from those of a simple single-user ISP connection
299 up to mail retrieval and rerouting for an entire client domain.
300 Fetchmail is easy to configure, unobtrusive in operation, powerful,
301 feature-rich, and well documented.</p>
303 <p>Fetchmail is <a href="http://www.opensource.org/">Open Source</a>
304 Software. The openness of the sources enables you to review and
305 customize the code, and contribute your changes.</p>
307 <p>A former fetchmail maintainer once claimed that Open Source software
308 were the strongest quality assurance, but the current maintainers do not
309 believe that open source alone is a criterion for quality – <a
310 href="fetchmail-SA-2005-01.txt">the remotely exploitable POP3
311 vulnerability (CVE-2005-2335)</a> lingered undiscovered in
312 fetchmail's code for years, which is a hint that open source code does
313 not audit itself.</p>
315 <p>Fetchmail is licensed under the <a
316 href="http://www.gnu.org/copyleft/gpl.html">GNU General Public
319 <p>If you found this FAQ in the distribution, see the README for
320 fetchmail's full feature list.</p>
322 <h2><a id="G2" name="G2">G2. Where do I find the latest FAQ and
323 fetchmail sources?</a></h2>
325 <p>The latest HTML FAQ is available alongside the latest fetchmail
326 sources at the fetchmail home page: <a
327 href="http://www.fetchmail.info/">http://www.fetchmail.info/</a>.
328 You can also usually find both in the <a
329 href="http://www.ibiblio.org/pub/Linux/system/mail/pop/!INDEX.short.html">
330 POP mail tools directory on iBiblio</a>.</p>
332 <p>A text dump of this FAQ is included in the fetchmail
333 distribution. Because it freezes at distribution release time, it
334 may not be completely current.</p>
336 <h2><a id="G3" name="G3">G3. I think I've found a bug. Will you fix
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>A copy of your POP or IMAP server's greeting line.</li>
358 <li>The name and version of the SMTP listener or MDA you are
361 <li>Any command-line options you used.</li>
363 <li>The output of fetchmail -V called with whatever other
364 command-line options you used.</li>
367 <p>If you have FTP access to your remote mail account, and you have
368 any suspicion that the bug was triggered by a particular message,
369 please include a copy of the message that triggered the bug.</p>
371 <p>If your bug is something that used to work but stopped working
372 when you upgraded, then you can help pin the bug down by trying <a
373 href="http://download.berlios.de/fetchmail/">intermediate versions
374 of fetchmail</a> until you identify the revision that broke your
375 feature. The smart way to do this is by binary search on the
376 version sequence. First, try the version halfway between your last
377 good one and the current one. If it works, the failure was
378 introduced in the upper half of the sequence; if it doesn't, the
379 failure was introduced in the lower half. Now bisect that half in
380 the same way. In a very few tries, you should be able to identify
381 the exact adjacent pair of versions between which your bug was
382 introduced – and with information like that, I can usually come up
383 with a fix very quickly.</p>
385 <p>Another useful thing you can do, if you're using POP3, is to
386 test for IMAP4 support on your mailserver using the autoprobe
387 function of fetchmailconf. If you have IMAP4, and fetchmailconf
388 doesn't tell you it's broken, switch immediately. POP3 is a weak,
389 poorly-designed protocol with chronic problems, and the later
390 versions after RFC1725 actually get worse rather than better.
391 Changing over to IMAP4 may well make your problem go away – and if
392 your ISP doesn't have IMAP4 support, bug them to supply it.</p>
394 <p>It is helpful if you include your .fetchmailrc file, but not
395 necessary unless your symptom seems to involve an error in
396 configuration parsing. If you do send in your .fetchmailrc, mask
397 the passwords first!</p>
399 <p>If fetchmail seems to run and fetch mail, but the headers look
400 mangled (that is, headers are missing or blank lines are inserted
401 in the headers) then read the FAQ items in section <a
402 href="#X1">X</a> before submitting a bug report. Pay special
403 attention to the item on <a href="#generic_mangling">diagnosing
404 mail mangling</a>. There are lots of ways for other programs in the
405 mail chain to screw up that look like fetchmail's fault, but you
406 may be able to fix these by tweaking your configuration.</p>
408 <p>A transcript of the failed session with "--nosyslog --nodetach -vvv"
409 (yes, that's <em>three</em> -v options, enabling debug mode) will almost
410 always be useful. It is very important that the transcript include your
411 POP/IMAP server's greeting line, so I can identify it in case of server
412 problems. This transcript will not reveal your passwords, which are
413 specially masked out precisely so transcripts can be passed around.</p>
415 <p>If you upgraded your fetchmail and something broke, you should
416 include session transcripts with "--nosyslog --nodetach -vvv" of both
417 the working and failing versions. Very often, the source of the problem
418 can instantly identified by looking at the differences in protocol
421 <p>If the bug involves a core dump or hang, a gdb stack trace is
422 good to have. (Bear in mind that you can attach gdb to a running
423 but hung process by giving the process ID as a second argument.)
424 You will need to reconfigure with:</p>
427 CFLAGS=-g LDFLAGS=" " ./configure
430 <p>Then rebuild in order to generate a version that can be
431 traced with a debugger such as gdb, dbx or idb.</p>
433 <p>Best of all is a mail file which, when fetched, will reproduce
434 the bug under the latest (current) version.</p>
436 <p>Any bug I can reproduce will usually get fixed quite quickly.
437 Bugs I can't reproduce are a crapshoot. If the solution isn't obvious
438 when I first look, it may evade me for a long time (or to put it another
439 way, fetchmail is well enough tested that the easy bugs have long since
440 been found). So if you want your bug fixed rapidly, it is not just
441 sufficient but <em>necessary</em> that you give me a way to
442 easily reproduce it.</p>
444 <h2><a id="G4" name="G4">G4. I have this idea for a neat feature.
445 Will you add it?</a></h2>
447 <p>If it's reasonable for fetchmail and cannot be solved with reasonable
448 effort outside of fetchmail, perhaps.</p>
450 <p>You can do spam filtering better with procmail or maildrop on
451 the server side and (if you're the server sysadmin) sendmail.cf
452 domain exclusions. If you really want fetchmail to do it from the
453 client side, use a <code>preconnect</code> command to call
454 <a href='http://mailfilter.sourceforge.net/'>mailfilter</a>.</p>
456 <p>You can do other policy things better with the
457 <code>mda</code> option and script wrappers around fetchmail. If
458 it's a prime-time-vs.-non-prime-time issue, ask yourself whether a
459 wrapper script called from crontab would do the job.</p>
461 <p>fetchmail's first job is transport though, and it should do this
462 well. If a feature would cause fetchmail to deteriorate in other
463 respects, the feature will probably not be added.</p>
465 <p>For reasons fetchmail doesn't have other commonly-requested
466 features (such as password encryption, or multiple concurrent polls
467 from the same instance of fetchmail) see <a
468 href="esrs-design-notes.html">ESR's design
469 notes</a>. Note that this document is partially obsoleted by the
470 <a href="design-notes.html">updated design notes.</a></p>
472 <h2><a id="G5" name="G5">G5. I want to make fetchmail behave like
473 Outlook Express.</a></h2>
475 <p>The second-most-requested feature for fetchmail, after
476 content-based filtering, is the ability to have it remove messages
477 from a maildrop after N days, typically to be used with the
478 <code>keep</code> option as a sort of poor man's newsgroup
479 facility. Microsoft's Outlook Express supports this.</p>
481 <p>This feature is not yet implemented. It may be at a future date,
482 spare time of developers permitting.</p>
484 <h2><a id="G6" name="G6">G6. Is there a mailing list for exchanging
487 <p>There is a fetchmail-users list
488 <fetchmail-users@lists.berlios.de>
489 for bug reports and people who want to discuss configuration issues of
490 fetchmail. It's a Mailman list, see <a
491 href="http://lists.berlios.de/mailman/listinfo/fetchmail-users">http://lists.berlios.de/mailman/listinfo/fetchmail-users</a>.</p>
492 <p>There is a fetchmail-devel list
493 <fetchmail-devel@lists.berlios.de> for people who want to discuss
494 fixes and improvements in fetchmail and help co-develop it. It's a
495 Mailman list, which you can sign up for at <a
496 href="http://lists.berlios.de/mailman/listinfo/fetchmail-devel">http://lists.berlios.de/mailman/listinfo/fetchmail-devel</a>.
497 There is also an announcements-only list,
498 <fetchmail-announce@lists.berlios.de>, which you can sign up for at <a
499 href="http://lists.berlios.de/mailman/listinfo/fetchmail-announce">http://lists.berlios.de/mailman/listinfo/fetchmail-announce</a>.</p>
501 <h2><a id="G7" name="G7">G7. So, what's this I hear about a
502 fetchmail paper?</a></h2>
504 <p>Eric S. Raymond also considered fetchmail development a sociological
505 experiment, an extended test to see if my theory about the critical
506 features of the Linux development model is correct.</p>
508 <p>He considers the experiment a success. He wrote a paper about it titled <a
509 href="http://www.catb.org/~esr/writings/cathedral.html">The
510 Cathedral and the Bazaar</a> which was first presented at Linux
511 Kongress '97 in Bavaria and very well received there. It was also
512 given at Atlanta Linux Expo, Linux Pro '97 in Warsaw, and the first
513 Perl Conference, at UniForum '98, and was the basis of an invited
514 presentation at Usenix '98. The folks at Netscape told ESR it helped
516 href="http://wp.netscape.com/newsref/pr/newsrelease558.html">give
517 away the source for Netscape Communicator</a>.</p>
519 <p>If you're reading a non-HTML dump of this FAQ, you can find the
520 paper on the Web with a search for that title.</p>
522 <h2><a id="G8" name="G8">G8. What is the best server to use with
525 <p>Fetchmail will work with any POP, IMAP, ETRN, or ODMR server
526 that conforms to the relevant standards/RFCs (and even some outright
527 broken ones like <a href="#S2">Microsoft Exchange</a> and <a
528 href="#S6">Novell GroupWise</a>). This doesn't mean it works equally
529 well with all, however. POP2 servers, and POP3 servers without UIDL,
530 limit fetchmail's capabilities in various ways described on the manual
533 <p>Most modern Unixes (and effectively all Linux/*BSD systems) come
534 with POP3 support preconfigured (but beware of the horribly broken
535 POP3 server mentioned in <a href="#D2">D2</a>). An increasing
536 minority also feature IMAP (you can detect IMAP support by using the
537 'Probe for supported protocols' function in the fetchmailconf
538 utility - unfortunately it does not detect SSL-wrapped variants).</p>
540 <p>If you have the option, we recommend using or installing an
541 IMAP4rev1 or UIDL- and TOP-capable POP3 server. IMAP enables some
542 significant performance optimizations.</p>
544 <p>Don't be fooled by NT/Exchange propaganda. M$ Exchange is just
545 plain broken (see item <a href="#S2">S2</a>) and NT cannot handle
546 the sustained load of a high-volume remote mail server. Even
547 Microsoft itself knows better than to try this; their own Hotmail
548 service runs over Solaris! For extended discussion, see John
549 Kirch's excellent <a href="http://unix-vs-nt.org/kirch/">white
550 paper</a> on Unix vs. NT performance.</p>
552 <p>A decent POP3/IMAP server that has recently become popular is <a
553 href="http://dovecot.org/">Dovecot</a>.</p>
555 <p>Avoid <a href="http://home.pages.de/~mandree/qmail-bugs.html">qmail,
556 it's broken and unmaintained.</a></p>
558 <h2><a id="G9" name="G9">G9. What is the best mail program to use
559 with fetchmail?</a></h2>
561 <p>Fetchmail will work with all popular <a href="#T1">mail
562 transport programs</a>. It also doesn't care which user agent you
563 use, and user agents are as a rule almost equally indifferent to
564 how mail is delivered into your system mailbox. So any of the
565 popular Unix mail agents – <a
566 href="http://www.instinct.org/elm/">elm</a>, <a
567 href="http://www.washington.edu/pine/">pine</a>, <a
568 href="http://www.cs.indiana.edu/docproject/mail/mh.html">mh</a>, or
569 <a href="http://www.mutt.org">mutt</a> – will work fine with
572 <p>All this having been said, I can't resist putting in a discreet
573 plug for <a href="http://www.mutt.org">mutt</a>. Mutt's interface
574 is only a little different from that of its now-moribund ancestor
575 elm, but its flexibility and excellent handling of MIME and PGP put it
576 in a class by itself. You won't need its built-in POP3 support, though.
579 <h2><a id="G10" name="G10">G10. How can I avoid sending my password
582 <p>Depending on what your mail server you are talking to, this
583 ranges from trivial to impossible. It may even be next to
586 <p>In general there is little point in trying to secure your fetchmail
587 transaction unless you trust the security of the server host you are
588 retrieving mail from. Your vulnerability is more likely to be an
589 insecure local network on the server end (e.g. to somebody with a
590 TCP/IP packet sniffer intercepting Ethernet traffic between the modem
591 concentrator or DSL POP you dial in to and the mailserver host).</p>
593 <p>Having realized this, you need to ask whether password
594 encryption alone will really address your security exposure. If you
595 think you might be snooped between server and client, it's better
596 to use end-to-end encryption such as GnuPG (see below) on your whole
597 mail stream so none of it can be read. One of the advantages of
598 fetchmail over conventional SMTP-push delivery is that you may be able
599 to arrange encryption by using ssh(1); see <a href="#K3">K3</a>.</p>
601 <p>Note that ssh is not a complete privacy solution either, as your
602 mail could have been snooped in transit to your POP server from
603 wherever it originated. For best security, agree with your
604 correspondents to use a tool such as <a
605 href="http://www.gnupg.org/">GnuPG</a> (Gnu Privacy Guard) or PGP
606 (Pretty Good Privacy).</p>
608 <p>If ssh/sshd isn't available, or you find it too complicated for
609 you to set up, password encryption will at least keep a malicious
610 cracker from deleting your mail, and require him to either tap your
611 connection continuously or crack root on the server in order to
614 <p>You can deduce what encryptions your mail server has available
615 by looking at the server greeting line (and, for IMAP, the response
616 to a CAPABILITY query). Do a <code>fetchmail -v</code> to see
617 these, or telnet direct to the server port (110 for POP3, 143 for
620 <p>If your mailserver is using IMAP 2000, it'll have CRAM-MD5
621 support built in. Fetchmail autodetects this; you can skip the rest
624 <p>The POP3 facility you are most likely to have available is APOP.
625 This is a POP3 feature supported by many servers (fetchmailconf's
626 autoprobe facility will detect it and tell you if you have it). If
627 you see something in the greeting line that looks like an
628 angle-bracket-enclosed Internet address with a numeric left-hand
629 part, that's an APOP challenge (it will vary each time you log in).
630 For some hosts, you need to register a secret on the host (using
631 <code>popauth(8)</code> or some program like that). Specify the
632 secret as your password in your .fetchmailrc; it will be used to
633 encrypt the current challenge, and the encrypted form will be sent
634 back the the server for verification. Note that APOP is no longer
635 considered secure since March 2007.</p>
637 <p>Alternatively, you may have Kerberos available. This may require
638 you to set up some magic files in your home directory on your
639 client machine, but means you can omit specifying any password at
642 <p>Fetchmail supports two different Kerberos schemes. One is a POP3
643 variant called KPOP; consult the documentation of your mail server
644 to see if you have it (one clue is the string "krb-IV" in the
645 greeting line on port 110). The other is an IMAP and POP3 facility
646 described by RFC1731 and RFC1734. You can tell if this one is
647 present by looking for AUTH=KERBEROS_V4 in the CAPABILITY
650 <p>If you are fetching mail from a CompuServe POP3 account, you can
651 use their RPA authentication. See <a href="#I1">I1</a> for details.
652 If you are fetching mail from
653 Microsoft Exchange using IMAP, you will be able to use NTLM.</p>
655 <p>Your POP3 server may have the RFC1938 OTP capability to use
656 one-time passwords (if it doesn't, you can get OTP patches for the
657 2.2 version of the Qualcomm popper from <a href="#cmetz">Craig
658 Metz</a>). To check this, look for the string "otp-" in the
659 greeting line. If you see it, and your fetchmail was built with
660 OPIE support compiled in (see the distribution INSTALL file),
661 fetchmail will detect it also. When using OTP, you will specify a
662 password but it will not be sent en clair.</p>
664 <p>You can get both POP3 and IMAP OTP patches from <a id="cmetz"
665 name="cmetz">Craig Metz</a> at <a
666 href="http://www.inner.net/opie">http://www.inner.net/opie</a>.</p>
668 <p>These patches use a SASL authentication method named "X-OTP"
669 because there is not currently a standard way to do this; fetchmail
670 also uses this method, so the two will interoperate happily. They
671 better, because this is how Craig gets his mail ;-)</p>
673 <p>Finally, you can use <a href="#K5">SSL</a> for complete
674 end-to-end encryption if you have an SSL-enabled mailserver.</p>
676 <h2><a id="G11" name="G11">G11. Is any special configuration needed
677 to use a dynamic IP address?</a></h2>
679 <p>Yes. In order to avoid giving indigestion to certain picky MTAs
680 (notably <a href="#T3">exim</a>), fetchmail always makes the RCPT TO
681 address it feeds the MTA a fully qualified one with a hostname
682 part. Normally it does this by appending @ and "localhost", but
683 when you are using Kerberos or ETRN mode it will append @ and your
684 machine's fully-qualified domain name (FQDN).</p>
686 <p>Appending the FQDN can create problems when fetchmail is running
687 in daemon mode and outlasts the dynamic IP address assignment your
688 client machine had when it started up.</p>
690 <p>Since the new IP address (looked up at RCPT TO interpretation
691 time) doesn't match the original, the most benign possible result
692 is that your MTA thinks it's seeing a relaying attempt and refuses.
693 More frequently, fetchmail will try to connect to a nonexistent
694 host address and time out. Worst case, you could up forwarding your
695 mail to the wrong machine!</p>
697 <p>Use the <code>smtpaddress</code> option to force the appended
698 hostname to one with a (fixed) IP address of 127.0.0.1 in your
699 <code>/etc/hosts</code>. (The name 'localhost' will usually work;
700 or you can use the IP address itself.)</p>
702 <p>Only one fetchmail option interacts directly with your IP
703 address, '<code>interface</code>'. This option can be used to set
704 the gateway device and restrict the IP address range fetchmail will
705 use. Such a restriction is sometimes useful for security reasons,
706 especially on multihomed sites. See <a href="#C3">C3</a>.</p>
708 <p>I recommend against trying to set up the <code>interface</code>
709 option when initially developing your poll configuration – it's
710 never necessary to do this just to get a link working. Get the link
711 working first, observe the actual address range you see on
712 connections, and add an <code>interface</code> option (if you need
715 <p>You can't use ETRN if you have a dynamic IP address (your ISP
716 changes your IP address occasionally, possibly with every connect).
717 You need to have your own registered domain and a definite IP
718 address registered for that domain. The server needs to be
719 configured to accept mail for your domain but then queue it to
720 forward to your machine. ETRN just tells to server to flush its
721 queue for your domain. Fetchmail doesn't actually get the mail in
724 <p>You can use On-Demand Mail Relay (ODMR) with a dynamic IP
725 address; that's what it was designed for, and it provides
726 capabilities very similar to ETRN. Unfortunately ODMR servers are
727 still not yet widely deployed, as of 2006.</p>
729 <p>If you're using a dynamic-IP configuration, one other
730 (non-fetchmail) problem you may run into with outgoing mail is that
731 some sites will bounce your email because the hostname you're giving
732 them isn't real (and doesn't match what they get doing a reverse
733 DNS on your dynamically-assigned IP address). If this happens, you
734 need to hack your sendmail so it masquerades as your host.
741 <p>in your <code>sendmail.cf</code> will work, or you can set</p>
744 MASQUERADE_AS(smarthost.here)
747 <p>in the m4 configuration and do a reconfigure. (In both cases,
748 replace <code>smarthost.here</code> with the actual name of your
749 mailhost.) See the <a
750 href="http://www.lege.com/sendmail-FAQ.txt">sendmail FAQ</a> for
753 <h2><a id="G12" name="G12">G12. Is any special configuration needed
754 to use firewalls?</a></h2>
756 <p>No. You can use fetchmail with SOCKS, the standard tool for
757 indirecting TCP/IP through a firewall. You can find out about
758 SOCKS, and download the SOCKS software including server and client
759 code, at the <a href="http://www.socks.nec.com/">SOCKS distribution
762 <p>The specific recipe for using fetchmail with a firewall is at <a
763 href="#K1">K1</a></p>
765 <h2><a id="G13" name="G13">G13. Is any special configuration needed
766 to <em>send</em> mail?</a></h2>
768 <p>A user asks: but how do we send mail out to the POP3 server? Do
769 I need to implement another tool or will fetchmail do this too?</p>
771 <p>Fetchmail only handles the receiving side. The sendmail or other
772 preinstalled MTA on your client machine will handle sending mail
773 automatically; it will ship mail that is submitted while the
774 connection is active, and put mail that is submitted while the
775 connection is inactive into the outgoing queue.</p>
777 <p>Normally, sendmail is also run periodically (every 15 minutes on
778 most Linux systems) in a mode that tries to ship all the mail in
779 the outgoing queue. If you have set up something like pppd to
780 automatically dial out when your kernel is called to open a TCP/IP
781 connection, this will ensure that the mail gets out.</p>
783 <h2><a id="G14" name="G14">G14. Is fetchmail
784 Y2K-compliant?</a></h2>
786 <p>Fetchmail is fully Y2K-compliant.</p>
788 <p>Fetchmail could theoretically have problems when the 32-bit
789 time_t counters roll over in 2038, but I doubt it. Timestamps
790 aren't used for anything but log entry generation. Anyway, if you
791 aren't running on a 64-bit machine by then, you'll deserve to
794 <h2><a id="G15" name="G15">G15. Is there a way in fetchmail to
795 support disconnected IMAP mode?</a></h2>
797 <p>No. Fetchmail is a mail transport agent, best understood as a
798 protocol gateway between POP3/IMAP servers and SMTP. Disconnected
799 operation requires an elaborate interactive client. It's a very
800 different problem.</p>
802 <h2><a id="G16" name="G16">G16. How will fetchmail perform under
803 heavy loads?</a></h2>
805 <p>Fetchmail streams message bodies line-by-line; the most core it
806 ever requires per message is enough memory to hold the RFC822
807 header, and that storage is freed when body processing begins. It
808 is, accordingly, quite economical in its use of memory. It will store
809 the UID or UIDL data in core however, which can become considerable if
810 you are keeping lots of messages on the server.</p>
812 <p>After startup time, a fetchmail running in daemon mode stats its
813 configuration file once per poll cycle to see whether it has
814 changed and should be rescanned. Other than that, a fetchmail in
815 normal operation doesn't touch the disk at all; that job is left up
816 to the MTA or MDA the fetchmail talks to.</p>
818 <p>Fetchmail's performance is usually bottlenecked by latency on
819 the POP server or (less often) on the TCP/IP link to the server.
820 This is not a problem readily solved by tuning fetchmail, or even
821 by buying more TCP/IP capacity (which tends to improve bandwidth
822 but not necessarily latency).</p>
825 <h1>Build-time problems</h1>
826 <h2><a id="B1" name="B1"><strike>B1. Make coughs and dies when building on
827 FreeBSD.</strike></a></h2>
829 <p style="font-style:italic;">As of release 6.3.0, fetchmail's
830 Makefile[.in] should work flawlessly with BSD's portable make used on
831 FreeBSD. With older releases, use GNU make (usually installed as
832 <code>gmake</code>; otherwise try <kbd>pkg_add -r gmake</kbd>).</p>
834 <h2><a id="B2" name="B2">B2. Lex bombs out while building the
835 fetchmail lexer.</a></h2>
837 <p>fetchmail 6.3.0 and newer ship with the lexer and parser in .c
838 formats, so you do not need to use lex unless you hacked the .l or .y
841 <p>fetchmail's lexer has been developed with GNU flex and uses some of
842 its specialties, so the lexer cannot be compiled with the lex tools
843 shipped by some UNIX vendors (HP, SGI, Sun).</p>
845 <h2><a id="B3" name="B3">B3. I get link failures when I try to
846 build fetchmail.</a></h2>
848 <p>If you get errors resembling these:</p>
851 mxget.o(.text+0x35): undefined referenceto '__res_search'
852 mxget.o(.text+0x99): undefined reference to '__dn_skipname'
853 mxget.o(.text+0x11c): undefined reference to '__dn_expand'
854 mxget.o(.text+0x187): undefined reference to '__dn_expand'
855 make: *** [fetchmail] Error 1
858 <p>then you must add "-lresolv" to the LOADLIBS line in your
859 Makefile once you have installed the 'bind' package.</p>
861 <p>If you get link errors involving <tt>dcgettext</tt>, like
865 rcfile_y.o: In function 'yyparse':
866 rcfile_y.o(.text+0x3aa): undefined reference to 'dcgettext__'
867 rcfile_y.o(.text+0x4f2): undefined reference to 'dcgettext__'
868 rcfile_y.o(.text+0x5ee): undefined reference to 'dcgettext__'
869 rcfile_y.o: In function 'yyerror':
870 rcfile_y.o(.text+0xc7c): undefined reference to 'dcgettext__'
871 rcfile_y.o(.text+0xcc8): undefined reference to 'dcgettext__'
872 rcfile_y.o(.text+0xdf9): more undefined references to 'dcgettext__' follow
875 <p>install an up to date version of GNU gettext, reconfigure and rebuild
876 fetchmail. If that does not help, reconfigure with '--disable-nls' added
877 to the "./configure" command and rebuild.</p>
879 <h2><a id="B4" name="B4">B4. I get build failures in the intl
882 <p>Reconfigure with <tt>--disable-nls</tt> and recompile.</p>
885 <h1>Fetchmail configuration file grammar questions</h1>
886 <h2><a id="F1" name="F1">F1. Why does my old .fetchmailrc file no
887 longer work?</a></h2>
889 <h3>If your file predates 6.3.0</h3>
891 <p>The <tt>netsec</tt> option was discontinued and needs to be
894 <h3>If your file predates 5.8.9</h3>
896 <p>If you were using ETRN mode, change your <tt>smtphost</tt>
897 option to a <tt>fetchdomains</tt> option.</p>
899 <h3>If your file predates 5.8.3</h3>
901 <p>The <tt>'via localhost'</tt> special case for use with ssh tunnelling is
902 gone. Use the <tt>%h</tt> feature of <tt>plugin</tt> instead.</p>
904 <h3>If your file predates 5.6.8</h3>
906 <p>In 5.6.8, the <tt>preauth</tt> keyword and option were changed
907 back to <tt>auth</tt>. The <tt>preauth</tt> synonym will still be
908 supported through a few more point releases.</p>
910 <h3>If your file predates 5.6.5</h3>
912 <p>The <tt>imap-gss</tt>, <tt>imap-k4</tt>, and <tt>imap-login</tt>
913 protocol types are gone. This is a result of a major re-factoring
914 of the authentication machinery; fetchmail can now use Kerberos V4
915 and GSSAPI not just with IMAP but with POP3 servers that have
916 RFC1734 support for the AUTH command.</p>
918 <p>When trying to identify you to an IMAP or POP mailserver,
919 fetchmail now first tries methods that don't require a password
920 (GSSAPI, KERBEROS_IV); then it looks for methods that mask your
921 password (CRAM-MD5, X-OTP); and only if it the server doesn't
922 support any of those will it ship your password en clair.</p>
924 <p>Setting the <tt>preauth</tt> option to any value other than
925 'password' will prevent from looking for a password in your
926 <tt>.netrc</tt> file or querying for it at startup time.</p>
928 <h3>If your file predates 5.1.0</h3>
930 <p>In 5.1.0, the <tt>auth</tt> keyword and option were changed to
931 <tt>preauth</tt>.</p>
933 <h3>If your file predates 4.5.5</h3>
935 <p>If the <code>dns</code> option is on (the default), you may need
936 to make sure that any hostname you specify (for mail hosts or for
937 an SMTP target) is a canonical fully-qualified hostname). In order
938 to avoid DNS overhead and complications, fetchmail no longer tries
939 to derive the fetchmail client machine's canonical DNS name at
942 <h3>If your file predates 4.0.6:</h3>
944 <p>Just after the '<code>via</code>' option was introduced, I
945 realized that the interactions between the '<code>via</code>',
946 '<code>aka</code>', and '<code>localdomains</code>' options were
947 out of control. Their behavior had become complex and confusing, so
948 much so that I was no longer sure I understood it myself. Users
949 were being unpleasantly surprised.</p>
951 <p>Rather than add more options or crock the code, I re-thought it.
952 The redesign simplified the code and made the options more
953 orthogonal, but may have broken some complex multidrop
956 <p>Any multidrop configurations that depended on the name just
957 after the '<code>poll</code>' or '<code>skip</code>' keyword being
958 still interpreted as a DNS name for address-matching purposes, even
959 in the presence of a '<code>via</code>' option, will break.</p>
961 <p>It is theoretically possible that other unusual configurations
962 (such as those using a non-FQDN poll name to generate Kerberos IV
963 tickets) might also break; the old behavior was sufficiently murky
964 that we can't be sure. If you think this has happened to you,
965 contact the maintainer.</p>
967 <h3>If your file predates 3.9.5:</h3>
969 <p>The '<code>remote</code>' keyword has been changed to
970 '<code>folder</code>'. If you try to use the old keyword, the
971 parser will utter a warning.</p>
973 <h3>If your file predates 3.9:</h3>
975 <p>It could be because you're using a .fetchmailrc that's written
976 in the old popclient syntax without an explicit
977 '<code>username</code>' keyword leading the first user entry
978 attached to a server entry.</p>
980 <p>This error can be triggered by having a user option such as
981 '<code>keep</code>' or '<code>fetchall</code>' before the first
982 explicit username. For example, if you write</p>
985 poll openmail protocol pop3
986 keep user "Hal DeVore" there is hdevore here
989 <p>the '<code>keep</code>' option will generate an entire user
990 entry with the default username (the name of fetchmail's invoking
993 <p>The popclient compatibility syntax was removed in 4.0. It
994 complicated the configuration file grammar and confused users.</p>
996 <h3>If your file predates 2.8:</h3>
998 <p>The '<code>interface</code>', '<code>monitor</code>' and
999 '<code>batchlimit</code>' options changed after 2.8.</p>
1001 <p>They used to be global options with '<code>set</code>' syntax
1002 like the batchlimit and logfile options. Now they're per-server
1003 options, like '<code>protocol</code>'.</p>
1005 <p>If you had something like</p>
1008 set interface = "sl0/10.0.2.15"
1011 <p>in your .fetchmailrc file, simply delete that line and insert
1012 'interface sl0/10.0.2.15' in the server options part of your
1013 'defaults' declaration.</p>
1015 <p>Do similarly for any '<code>monitor</code>' or
1016 '<code>batchlimit</code>' options.</p>
1018 <h2><a id="F2" name="F2">F2. The .fetchmailrc parser won't accept
1019 my all-numeric user name.</a></h2>
1021 <p>Either upgrade to a post-5.0.5 fetchmail or put string quotes
1024 <p>The configuration file parser in older fetchmail versions
1025 treated any all-numeric token as a number, which confused it when
1026 it was expecting a name. String quoting forces the token's
1029 <p>The lexical analyzer in 5.0.6 and beyond is smarter and assumes
1030 any token following "username" or "password" is a string.</p>
1032 <h2><a id="F3" name="F3">F3. The .fetchmailrc parser won't accept
1033 my host or username beginning with 'no'.</a></h2>
1035 <p>See <a href="#F2">F2</a>. You're caught in an unfortunate crack
1036 between the newer-style syntax for negated options ('no keep', 'no
1037 rewrite' etc.) and the older style run-on syntax ('nokeep',
1038 'norewrite' etc.).</p>
1040 <p>Upgrade to a 5.0.6 or later fetchmail, or put string quotes
1041 around your token.</p>
1043 <h2><a id="F4" name="F4">F4. I'm getting a 'parse error' message I
1044 don't understand.</a></h2>
1046 <p>The most common cause of mysterious parse errors is putting a
1047 server option after a user option. Check the manual page; you'll
1048 probably find that by moving one or more options closer to the
1049 'poll' keyword you can eliminate the problem.</p>
1051 <p>Yes, I know these ordering restrictions are hard to understand.
1052 Unfortunately, they're necessary in order to allow the 'defaults'
1053 feature to work.</p>
1056 <h1>Configuration questions</h1>
1057 <h2><a id="C1" name="C1">C1. Why do I need a .fetchmailrc when
1058 running as root on my own machine?</a></h2>
1060 <p>Ian T. Zimmerman <itz@rahul.net> asked:</p>
1062 <p>On the machine where I'm the only real user, I run fetchmail as
1063 root from a cron job, like this:</p>
1066 fetchmail -u "itz" -p POP3 -s bolero.rahul.net
1069 <p>This used to work as is (with no .fetchmailrc file in root's
1070 home directory) with the last version I had (1.7 or 1.8, I don't
1071 remember). But with 2.0, it RECPs all mail to the local root user,
1072 unless I create a .fetchmailrc in root's home directory
1076 skip bolero.rahul.net proto POP3
1080 <p>It won't work if the second line is just "<code>user
1081 itz</code>". This is silly.</p>
1083 <p>It seems fetchmail decides to RECP the 'default local user'
1084 (i.e. the uid running fetchmail) unless there are local aliases,
1085 and the 'default' aliases (itz->itz) don't count. They
1090 <p>No they shouldn't. I thought about this for a while, and I don't
1091 much like the conclusion I reached, but it's unavoidable. The
1092 problem is that fetchmail has no way to know, in general, that a
1093 local user 'itz' actually exists.</p>
1095 <p>"Ah!" you say, "Why doesn't it check the password file to see if
1096 the remote name matches a local one?" Well, there are two
1099 <p>One: it's not always possible. Suppose you have an SMTP host
1100 declared that's not the machine fetchmail is running on? You
1103 <p>Two: How do you know server itz and SMTP-host itz are the same
1104 person? They might not be, and fetchmail shouldn't assume they are
1105 unless local-itz can explicitly produce credentials to prove it
1106 (that is, the server-itz password in local-itz's .fetchmailrc
1109 <p>Once you start running down possible failure modes and thinking
1110 about ways to tinker with the mapping rules, you'll quickly find
1111 that all the alternatives to the present default are worse or
1112 unacceptably more complicated or both.</p>
1114 <h2><a id="C2" name="C2">C2. How can I arrange for a fetchmail
1115 daemon to get killed when I log out?</a></h2>
1117 <p>The easiest way to dispatch fetchmail on logout (which will work
1118 reliably only if you have just one login going at any time) is to
1119 arrange for the command 'fetchmail -q' to be called on logout.
1120 Under bash, you can arrange this by putting 'fetchmail -q' in the
1121 file '~/.bash_logout'. Most csh variants execute '~/.logout' on
1122 logout. For other shells, consult your shell manual page.</p>
1124 <p>Automatic startup/shutdown of fetchmail is a little harder to
1125 arrange if you may have multiple login sessions going. In the
1126 contrib subdirectory of the fetchmail distribution there is some
1127 shell code you can add to your .bash_login and .bash_logout
1128 profiles that will accomplish this. Thank James Laferriere
1129 <babydr@nwrain.net> for it.</p>
1131 <p>Some people start up and shut down fetchmail using the ppp-up
1132 and ppp-down scripts of pppd.</p>
1134 <h2><a id="C3" name="C3">C3. How do I know what interface and
1135 address to use with --interface?</a></h2>
1137 <p>This depends a lot on your local networking configuration (and
1138 right now you can't use it at all except under Linux and the newer
1139 BSDs). However, here are some important rules of thumb that can
1140 help. If they don't work, ask your local sysop or your Internet
1143 <p>First, you may not need to use --interface at all. If your
1144 machine only ever does SLIP or PPP to one provider, it's almost
1145 certainly by a point to point modem connection to your provider's
1146 local subnet that's pretty secure against snooping (unless someone
1147 can tap your phone or the provider's local subnet!). Under these
1148 circumstances, specifying an interface address is fairly
1151 <p>What the option is really for is sites that use more than one
1152 provider. Under these circumstances, typically one of your provider
1153 IP addresses is your mailserver (reachable fairly securely via the
1154 modem and provider's subnet) but the others might ship your packets
1155 (including your password) over unknown portions of the general
1156 Internet that could be vulnerable to snooping. What you'll use
1157 --interface for is to make sure your password only goes over the
1158 one secure link.</p>
1160 <p>To determine the device:</p>
1163 <li>If you're using a SLIP link, the correct device is probably
1166 <li>If you're using a PPP link, the correct device is probably
1169 <li>If you're using a direct connection over a local network such
1170 as an ethernet, use the command 'netstat -r' to look at your
1171 routing table. Try to match your mailserver name to a destination
1172 entry; if you don't see it in the first column, use the 'default'
1173 entry. The device name will be in the rightmost column.</li>
1176 <p>To determine the address and netmask:</p>
1179 <li>If you're talking to slirp, the correct address is probably
1180 10.0.2.15, with no netmask specified. (It's possible to configure
1181 slirp to present other addresses, but that's the default.)</li>
1183 <li>If you have a static IP address, run 'ifconfig <device>',
1184 where <device> is whichever one you've determined. Use the IP
1185 address given after "inet addr:". That is the IP address for your
1186 end of the link, and is what you need. You won't need to specify a
1189 <li>If you have a dynamic IP address, your connection IP will vary
1190 randomly over some given range (that is, some number of the least
1191 significant bits change from connection to connection). You need to
1192 declare an address with the variable bits zero and a complementary
1193 netmask that sets the range.</li>
1196 <p>To illustrate the rule for dynamic IP addresses, let's suppose
1197 you're hooked up via SLIP and your IP provider tells you that the
1198 dynamic address pool is 255 addresses ranging from 205.164.136.1 to
1199 205.164.136.255. Then</p>
1202 interface "sl0/205.164.136.0/255.255.255.0"
1205 <p>would work. To range over any value of the last two octets
1206 (65536 addresses) you would use</p>
1209 interface "sl0/205.164.0.0/255.255.0.0"
1212 <h2><a id="C4" name="C4">C4. How can I set up support for
1213 sendmail's anti-spam features?</a></h2>
1215 <p>This answer covers versions of sendmail from 8.9.3-20 (the
1216 version installed in Red Hat 6.2) upwards. If you have an older
1217 version, upgrade to sendmail 8.9.</p>
1219 <p>Stock sendmails can now do anti-spam exclusions based on a
1220 database of filter rules. The human-readable form of the database
1221 is at <tt>/etc/mail/access</tt>. The database itself is at
1222 <tt>/etc/mail/access.db</tt>.</p>
1224 <p>The table itself uses email addresses, domain names, and network
1225 numbers as keys. For example,</p>
1228 spammer@aol.com REJECT
1229 cyberspammer.com REJECT
1233 <p>would refuse mail from spammer@aol.com, any user from
1234 cyberspammer.com (or any host within the cyberspammer.com domain),
1235 and any host on the 192.168.212.* network. (This feature can be
1236 used to do other things as well; see the <a
1237 href="http://www.sendmail.org/m4/anti_spam.html">sendmail
1238 documentation</a> for details)</p>
1240 <p>To actually set up the database, run</p>
1243 makemap hash deny <deny
1246 <p>in /etc/mail.</p>
1248 <p>To test, send a message to your mailing address from that host
1249 and then pop off the message with fetchmail, using the -v argument.
1250 You can monitor the SMTP transaction, and when the FROM address is
1251 parsed, if sendmail sees that it is an address in spamlist,
1252 fetchmail will flush and delete it.</p>
1254 <p>Under no circumstances put your <strong>mailhost</strong> or
1255 <strong>any host you accept mail from</strong> using fetchmail into
1256 your reject file. You <strong>will</strong> lose mail if you do
1259 <h2><a id="C5" name="C5">C5. How can I poll some of my mailboxes
1260 more/less often than others?</a></h2>
1262 <p>Use the <cite>interval</cite> keyword on the ones that should be
1263 checked less often. For example, if you do a poll every 5 minutes,
1264 and want to poll some mailboxes every 5 minutes and some every 30
1265 minutes, use something like this:</p>
1268 poll mainsite.example.com proto pop3 user ....
1269 poll secondary.example.com proto pop3 interval 6 user ...
1272 <p>Then secondary.example.com will be polled every 6th time that
1273 mainsite.example.com is polled, which with a polling interval of
1274 every 5 minutes means that secondary.example.com will be polled
1275 every 30 minutes.</p>
1277 <h2><a id="C6" name="C6">Fetchmail works OK started up manually,
1278 but not from an init script.</a></h2>
1280 <p>Often, startup scripts have a different environment than an
1281 interactive login shell. For instance, $HOME might point to "/root"
1282 when you are logged in as root, but it might be either unset, or
1283 set to "/" when the startup scripts are running. That means
1284 fetchmail at startup can't find the .fetchmailrc.</p>
1286 <p>Pick a location (such as /etc/fetchmailrc) and use fetchmail's
1287 -f option to point fetchmail at it. That should solve the
1290 <h2><a id="C7" name="C7">C7. How can I forward mail to another
1293 <p>To forward mail to a host other than the one you are running
1294 fetchmail on, use the <code>smtphost</code> or
1295 <code>smtpname</code> option. See the manual page for details.</p>
1298 <h1>How to make fetchmail play nice with various MTAs</h1>
1299 <h2><a id="T1" name="T1">T1. How can I use fetchmail with
1302 <p>For most sendmails, no special configuration is required. Eric
1303 Allman tells me that if <code>FEATURE(always_add_domain)</code> is
1304 included in sendmail's configuration, you can leave the
1305 <code>rewrite</code> option off.</p>
1307 <p>If your sendmail complains "sendmail does not relay", make
1308 sure your sendmail.cf file says <code>Cwlocalhost</code> so that
1309 sendmail recognizes 'localhost' as a name of its host.</p>
1311 <p>If you're mailing from another machine on your local network,
1312 also ensure that its IP address is listed in ip_allow or name in
1313 name_allow (usually in /etc/mail/)</p>
1315 <p>If you find that your sendmail doesn't like the address
1316 'FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail that
1317 fetchmail generates), you may have to set
1318 <code>FEATURE(accept_unqualified_senders)</code>.</p>
1320 <p>Günther Leber reports that Digital Unix sendmails won't
1321 work with fetchmail. The symptom is an error message "<code>553
1322 Local configuration error, hostname not recognized as
1323 local</code>". The problem is that fetchmail normally feeds
1324 sendmail with the client machine's host address in the MAIL FROM
1325 line. These sendmails think this means they're seeing the result of
1326 a mail loop and suppress the mail. You may be able to work around
1327 this by running in <code>--invisible</code> mode.</p>
1329 <p>If you want to support multidrop mode, and you can get access to
1330 your mailserver's sendmail.cf file, it's a good idea to add this
1334 H?l?Delivered-To: $h
1337 <p>This will cause the mailserver's sendmail to reliably write the
1338 appropriate envelope address into each message before fetchmail
1339 sees it, and tell fetchmail which header it is.  With this
1340 change, multidrop mode should work reliably even when the Received
1341 header omits the envelope address (which will typically be the case
1342 when the message has multiple recipients).  However it will
1343 still not distinguish the recipients, your only advantage is that
1344 no bounce will be sent if a message is BCC addressed to multiple
1345 users at your site.  To fix even that problem, you might want
1346 to try the following hack, which is however untested and quite
1350 H?J?Delivered-To: $u
1352 Mmdrop, P=/usr/bin/procmail, F=lsDFMqSPfhnu9J,
1353 S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP/HdrToSMTP,
1354 T=DNS/RFC822/X-Unix,
1355 A=procmail -Y -a $u -d $h
1358 <p>For both hacks, you have to declare '<code>envelope
1359 "Delivered-To:"</code>' on the fetchmail side, to put the virtual
1360 domain (e.g. 'domain.com') with RELAY permission into your access
1361 file and to add a line reading '<code>domain.com
1362 local:local-pop-user</code>' for the first and '<code>domain.com
1363 mdrop:local-pop-user</code>' for the second hack to your
1366 <p>You will notice that if the mail already has a Delivered-To
1367 header, sendmail will not add another.  Further, editing
1368 sendmail.cf directly is not very comfortable.  Solutions for
1369 both problems can be found in Peter 'Rattacresh' Backes' 'hybrid'
1370 patch against sendmail.  Have a look at it, you can find it in
1371 the contrib subdirectory.</p>
1373 <p>Feel free to try Martijn Lievaart's detailed recipe in the
1374 contrib subdirectory of the fetchmail source distribution, it
1375 attempts to realize multidrop mailboxes with an external
1378 <p>If for some reason you are invoking sendmail via the
1379 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
1380 don't forget to include the -i switch. Otherwise you will
1381 occasionally get mysterious delivery failures with a SIGPIPE as the
1382 sendmail instance dies. The problem is messages with a single dot
1383 at start of a text line.</p>
1385 <h2><a id="T2" name="T2">T2. How can I use fetchmail with
1388 <h3>qmail as your local SMTP server</h3>
1390 <p>Avoid <a href="http://home.pages.de/~mandree/qmail-bugs.html">qmail,
1391 it's broken and unmaintained.</a></p>
1393 <p>Turn on the <code>forcecr</code> option; qmail's listener mode
1394 doesn't like header or message lines terminated with bare
1396 (This information contributed by Robert de Bath
1397 <robert@mayday.cix.co.uk>.)</p>
1399 <h3>qmail as your ISP's POP3 server</h3>
1401 <p>Note that qmail's POP3 server, as of version 1.03 and netqmail 1.05,
1402 miscalculates the message sizes, so you may see size-related fetchmail
1405 <p>If a mailhost is using the qmail package, then it is usually possible
1406 to set up one fetchmail link to reliably collect the mail for an entire
1409 <p>One of the basic features of qmail is the 'Delivered-To:'
1410 message header. Whenever qmail delivers a message to a local
1411 mailbox it puts the username and hostname of the envelope recipient
1412 on this line. One major reason for this is to prevent mail
1413 loops, the other is to transport envelope information which is essential
1414 for multidrop (domain-in-a-mailbox) schemes.</p>
1416 <p>To set up qmail to batch mail for a disconnected site, the
1417 ISP-mailhost will have normally put that site in its 'virtualhosts'
1418 control file so it will add a prefix to all mail addresses for this
1419 site. This results in mail sent to
1420 'username@userhost.userdom.example.com' having a 'Delivered-To:' line
1424 Delivered-To: mbox-userstr-username@userhost.userdom.example.com
1427 <p>A single host maildrop will be slightly simpler:</p>
1430 Delivered-To: mbox-userstr-username@userhost.example.com
1433 <p>The ISP can make the 'mbox-userstr-' prefix anything they choose
1434 but a string matching the user host name is likely.</p>
1436 <p>To use this line you must:</p>
1439 <li>Ensure the option '<code>envelope "Delivered-To"</code>' is in the fetchmail
1442 <li>Ensure the option '<code>qvirtual "mbox-userstr-"</code>' is
1443 in the fetchmail config file, in order to remove this prefix from the
1444 username. (added by Luca Olivetti)</li>
1446 <li>Ensure you have a <code>localdomains</code> option containing
1447 '<code>userdom.example.com</code>' or '<code>userhost.userdom.example.com</code>'
1451 <h2><a id="T3" name="T3">T3. How can I use fetchmail with
1454 <p>If you have <code>rewrite</code> on:</p>
1456 <p>There is an RFC1123 requirement that MAIL FROM and RCPT TO
1457 addresses you pass to it have to be canonical (e.g. with a fully
1458 qualified hostname part). Therefore fetchmail tries to pass fully
1459 qualified RCPT TO addresses. But exim does not by default accept
1460 'localhost' as a fully qualified domain. This can be fixed.</p>
1462 <p>In exim.conf, add 'localhost' to your local_domains declaration
1463 if it's not already present. For example, the author's site at
1464 thyrsus.com would have a line reading:</p>
1467 local_domains = thyrsus.com:localhost
1470 <p>If you have <code>rewrite</code> off:</p>
1472 <p>MAIL FROM is a potential problem if the MTAs upstream from your
1473 fetchmail don't necessarily pass canonicalized From and Return-Path
1474 addresses, and fetchmail's <code>rewrite</code> option is off. The
1475 specific case where this has come up involves bounce messages
1476 generated by sendmail on your mailer host, which have the
1477 (un-canonicalized) origin address MAILER-DAEMON.</p>
1479 <p>The right way to fix this is to enable the <code>rewrite</code>
1480 option and have fetchmail canonicalize From and Return-Path
1481 addresses with the mailserver hostname before exim sees them. This
1482 option is enabled by default, so it won't be off unless you turned
1485 <p>If you must run with <code>rewrite</code> off, there is a switch
1486 in exim's configuration files that allows it to accept domainless
1487 MAIL FROM addresses; you will have to flip it by putting the
1491 sender_unqualified_hosts = localhost
1494 <p>in the main section of the exim configuration file. Note that
1495 this will result in such messages having an incorrect domain name
1496 attached to their return address (your SMTP listener's hostname
1497 rather than that of the remote mail server).</p>
1499 <h2><a id="T4" name="T4">T4. How can I use fetchmail with
1502 <p>Smail 3.2 is very nearly plug-compatible with sendmail, and may
1503 work fine out of the box.</p>
1505 <p>We have one report that when processing multiple messages from a
1506 single fetchmail session, smail sometimes delivers them in an order
1507 other than received-date order. This can be annoying because it
1508 scrambles conversational threads. This is not fetchmail's problem,
1509 it is an smail 'feature' and has been reported to the maintainers
1512 <p>Very recent smail versions require an
1513 <code>-smtp_hello_verify</code> option in the smail config file.
1514 This overrides smail's check to see that the HELO address is
1515 actually that of the client machine, which is never going to be the
1516 case when fetchmail is in the picture. According to RFC1123 an SMTP
1517 listener <em>must</em> allow this mismatch, so smail's new behavior
1518 (introduced sometime between 3.2.0.90 and 3.2.0.95) is a bug.</p>
1520 <p>You may also need to say
1521 <code>-smtp_hello_broken_allow=127.0.0.1</code> in order for smail
1522 to accept the "localhost" that fetchmail normally appends to
1523 recipient addresses.</p>
1525 <h2><a id="T5" name="T5">T5. How can I use fetchmail with SCO's
1528 <p>MMDF itself is difficult to configure, but it turns out that
1529 connecting fetchmail to MMDF's SMTP channel isn't that hard. You
1531 href="http://aplawrence.com/Unixart/uucptofetch.html">MMDF
1532 recipe</a> that describes replacing a UUCP link with fetchmail
1535 <h2><a id="T6" name="T6">T6. How can I use fetchmail with Lotus
1538 <p>The Lotus Notes SMTP gateway tries to deduce when it should
1539 convert \n to \r\n, but its rules are not the intuitive and
1540 correct-for-RFC822 ones. Use 'forcecr'.</p>
1542 <h2><a id="T7" name="T7">T7. How can I use fetchmail with Courier
1545 <p>The courier mta doesn't like RCPT addresses that look like
1546 <code>someone@localhost</code>. Work around this with an
1547 <code>smtphost</code> or <code>smtpaddress</code>.</p>
1549 <h2><a name="T8">T8. How can I use fetchmail with vbmailshield?</a></h2>
1551 <p>vbmailshield's SMTP interpreter is broken. It doesn't understand RSET.</p>
1553 <p>As a workaround, you can set batchlimit to 1 so RSET is never used.</p>
1556 <h1>How to make fetchmail work with various servers</h1>
1557 <h2><a id="S1" name="S1"><strike>S1. How can I use fetchmail with
1558 qpopper?</strike></a></h2>
1560 <p><em>The information that used to be here was obsolete and dropped.</em></p>
1562 <h2><a id="S2" name="S2">S2. How can I use fetchmail with Microsoft
1565 <p>It's been reliably reported that Exchange 2000's POP3 support is
1566 so broken that it's unusable. One symptom is that messages without
1567 a terminating newline get the POP3 message termination dot emitted
1568 -- you guessed it -- right after the last character of the message,
1569 with no terminating newline added. This will hang fetchmail or any
1570 other RFC-compliant server. IMAP is alleged to work OK, though.</p>
1572 <p>Older versions of Exchange are semi-usable. They randomly drop
1573 attachments on the floor, though. Microsoft acknowledges this
1574 as a known bug and apparently has no plans to fix it.</p>
1576 <p>Fetchmail using IMAP supports the proprietary NTLM mode used
1577 with M$ Exchange servers. To enable this, configure fetchmail with
1578 the --enable-NTLM option and recompile it. Specify a user option
1579 value that looks like 'user@domain': the part to the left of the @
1580 will be passed as the username and the part to the right as the
1583 <p>M$ Exchange violates the POP3 and IMAP RFCs. Its LIST command
1584 does not reveal the real sizes of mail in the pop mailbox, but the
1585 sizes of the compressed versions in the exchange mail database
1586 (thanks to Arjan De Vet and Guido Van Rooij for alerting us to this
1589 <p>Fetchmail works with M$ Exchange, despite this brain damage. Two
1590 features are compromised. One is that the --limit option will not
1591 work right (it will check against compressed and not actual sizes).
1592 The other is that a too-small SIZE argument may be passed to your
1593 ESMTP listener, assuming you're using one (this should not be a
1594 problem unless the actual size of the message is above the
1595 listener's configured length limit).</p>
1597 <p>Somewhat belatedly, I've learned that there's supposed to be a
1598 registry bit that can fix this breakage:</p>
1601 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1602 System\Pop3 Compatibility
1605 <p>This is a bitmask that controls the variations from the standard
1606 protocol. The bits defined are:</p>
1609 <dt>0x00000001:</dt>
1611 <dd>Report exact message sizes for the LIST command</dd>
1613 <dt>0x00000002:</dt>
1615 <dd>Allow arbitrary linear whitespace between commands and
1618 <dt>0x00000004:</dt>
1620 <dd>Enable the LAST command</dd>
1622 <dt>0x00000008:</dt>
1624 <dd>Allow an empty PASS command (needed for users with blank
1625 passwords, but illegal in the protocol)</dd>
1627 <dt>0x00000010:</dt>
1629 <dd>Relax the length restrictions for arguments to commands
1630 (protocol requires 40, but some user names may be longer than
1633 <dt>0x00000020:</dt>
1635 <dd>Allow spaces in the argument to the USER command.</dd>
1638 <p>There's another one that may be useful to know about:</p>
1641 KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1642 System\Pop3 Performance
1646 <dt>0x00000001:</dt>
1648 <dd>Render messages to a temporary stream instead of sending
1649 directly from the database (should always be on)</dd>
1651 <dt>0x00000002: Flag unrenderable messages (instead of just failing
1652 commands) (should only be on if you are seeing the problems
1653 reported in KB Q168109)</dt>
1655 <dt>0x00000004:</dt>
1657 <dd>Return from the QUIT command before all messages have been
1661 <p>The Microsoft pod-person who revealed this information to me
1662 admitted that he couldn't find it anywhere in their public
1665 <p>Another specific problem we have seen with Exchange servers has
1666 as its symptom a response to LOGIN that says "NO Ambiguous Alias".
1667 Grant Edwards writes:</p>
1669 <p>This means that Exchange Server is too f*&#ing stupid to
1670 figure out which mailbox belongs to you. Instead of actually
1671 keeping track of which inbox belongs to which user, it uses some
1672 half-witted, guess-o-matic heuristic to try to guess your mailbox
1673 name from your username.</p>
1675 <p>In your case it doesn't work because your username maps to more
1676 than one mailbox. For some people it doesn't work because their
1677 username maps to zero mailboxes. This is yet another inept, lame,
1678 almost criminally negligent design decision from our friends in
1681 <p>You've got several options:</p>
1684 <li>Get your administrator to configure the server so that
1685 usernames and mailbox names are the same.</li>
1687 <li>Get your administrator to add an alias that maps your username
1688 explicitly to your mailbox name.</li>
1691 <p>But, the best option involves finding a server that runs better
1694 <h2><a id="S3" name="S3">S3. How can I use fetchmail with HP
1697 <p>No special configuration is required, but OpenMail versions
1698 prior to 6.0 have an annoying bug similar to the big one in <a
1699 href="#S2">Microsoft Exchange</a>. The message sizes it gives in
1700 the LIST are rounded to the nearest 1024 bytes. It also has a nasty
1701 habit of discarding headers it doesn't recognize, such as X- and
1702 Resent- headers.</p>
1704 <p>As with M$ Exchange, the only real fix for these problems is to
1705 get a POP (or preferably IMAP) server that isn't brain-dead.
1706 OpenMail's project manager claims these bugs have been fixed in
1709 <p>We've had a more recent report (December 2001) that the TOP
1710 command fails, returning only one line regardless of its argument,
1711 on something identifying itself as "OpenMail POP3 interface".</p>
1713 <h2><a id="S4" name="S4">S4. How can I use fetchmail with Novell GroupWise?</a></h2>
1715 <p>The Novell GroupWise IMAP server would be better named
1716 GroupFoolish; it is (according to the designer of IMAP) unusably
1717 broken. Among other things, it doesn't include a required content
1718 length in its BODY[TEXT] response.</p>
1720 <p>Fetchmail works around this problem, but we strongly recommend
1721 voting with your dollars for a server that isn't brain-dead.</p>
1723 <h2><a id="S5" name="S5">S5. How can I use fetchmail with
1724 InterChange?</a></h2>
1726 <p>You can't. At least not if you want to be able to see
1727 attachments. InterChange has a bug similar to the MailMax server (<a
1728 href="#S6">see below</a>):
1729 it reports the message length with attachments but doesn't download
1730 them on TOP or RETR.</p>
1732 <p>On Jan 9 2001, the people at InfiniteMail sent me mail informing
1733 me that their new 3.61.08 release of InterChange fixes this
1734 problem. I don't have any reports one way or the other yet.</p>
1736 <h2><a id="S6" name="S6">S6. How can I use fetchmail with MailMax?</a></h2>
1738 <p>You can't. At least not if you want to be able to see
1739 attachments. MailMax has a bug; it reports the message length with
1740 attachments but doesn't download them on TOP or RETR.</p>
1742 <p>Also, we're told that TOP sometimes fails to retrieve the entire
1743 message even when enough lines have been specified. The MailMax
1744 developers have acknowledged this bug as of 4 May 2000, but there
1745 is no fix yet. If you must use this server, force RETR with the
1746 <tt>fetchall</tt> option.</p>
1748 <h2><a id="S7" name="S7">S7. How can I use fetchmail with FTGate?</a></h2>
1750 <p>The FTGate V2 server (and possibly older versions as well) has a
1751 weird bug. It answers OK twice to a TOP request! Use the
1752 <code>fetchall</code> option to force use of RETR and work around
1756 <h1>How to fetchmail work with specific ISPs</h1>
1757 <h2><a id="I1" name="I1">I1. How can I use fetchmail with CompuServe RPA?</a></h2>
1759 <p>First, make sure your fetchmail has the RPA support compiled in.
1760 Stock fetchmail binaries (such as you might get from an RPM) don't.
1761 You can check this by looking at the output of <code>fetchmail
1762 -V</code>; if you see the string "+RPA" after the version ID you're
1763 good to go, otherwise you'll have to build your own from sources
1764 (see the INSTALL file in the source distribution for
1767 <p>Give your CompuServe pass-phrase in lower case as your password.
1768 Add '@compuserve.com' to your user ID so that it looks like 'user
1769 <UserID>@compuserve.com', where <UserID> can be either
1770 your numerical userID or your E-mail nickname. An RPA-enabled
1771 fetchmail will automatically check for csi.com in the POP server's
1772 greeting line. If that's found, and your user ID ends with
1773 '@compuserve.com', it will query the server to see if it is
1774 RPA-capable, and if so do an RPA transaction rather than a
1775 plain-text password handshake.</p>
1777 <p><strong>Warning:</strong> the debug (-v -v) output of fetchmail
1778 will show your pass-phrase in Unicode!</p>
1780 <p>These two .fetchmailrc entries show the difference between an
1781 RPA and non-RPA configuration:</p>
1784 # This version will use RPA
1785 poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1786 user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
1787 is LOCAL_USER here options fetchall stripcr
1789 # This version will not use RPA
1790 poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1791 user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
1792 is LOCAL_USER here options fetchall stripcr
1795 <h2><a id="I2" name="I2">I2. How can I use fetchmail with Demon
1796 Internet's SDPS?</a></h2>
1798 <h3>Single-drop mode</h3>
1800 <p>You can get fetchmail to download the email for just one user
1801 from Demon Internet's POP3 server by giving it a username
1802 consisting of your Demon user name followed by your account name,
1803 with an at-sign between them.</p>
1805 <p>For example, to download email for the user
1806 <philh@vision25.demon.co.uk>, you could use the following
1807 .fetchmailrc file:</p>
1810 set postmaster "philh"
1811 poll pop3.demon.co.uk with protocol POP3:
1812 user "philh@vision25" is philh
1815 <h3>Multi-drop mode</h3>
1817 <p>Demon Internet's SDPS service is an implementation of POP3. All
1818 messages have a Received: header added when they enter the
1819 maildrop, like this:</p>
1822 Received: from punt-1.mail.demon.net by mailstore for fred@xyz.demon.co.uk
1823 id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
1826 <p>To enable multi-drop mode you need to tell fetchmail that
1827 'mailstore' is the name of the host which accepted the mail, and
1828 let it know the hostname part(s) of your E-mail address. The
1829 following example assumes that your hostname is xyz.demon.co.uk,
1830 and that you have also bought "mail forwarding" for the domain
1831 my-company.co.uk (in which case your MTA must also be configured to
1832 accept mail sent to user@my-company.co.uk)</p>
1835 poll pop3.demon.co.uk proto pop3 aka mailstore no dns:
1836 localdomains xyz.demon.co.uk my-company.co.uk
1840 <p>Note that Demon may delete mail on the server which is more than
1841 30 days old; see their <a
1842 href="http://www.demon.net/helpdesk/producthelp/mail/sdps-tech.html/">POP3
1843 page</a> for details.</p>
1845 <h3>The SDPS extension</h3>
1847 <p>There's a different way to do multidrop. It's not necessary on
1848 Demon Internet, since fetchmail can parse Received addresses, but
1849 the person who implemented this didn't know that. It may be useful
1850 if Demon Internet ever changes mail transports.</p>
1852 <p>SDPS includes a non-standard extension for retrieving the
1853 envelope of a message (*ENV), which fetchmail optionally supports
1854 if compiled with the --enable-SDPS option. If you have it, the
1855 first line of the fetchmail -V response will include the string
1858 <p>Once you have SDPS compiled in, fetchmail in POP3 mode will
1859 automatically detect when it's talking to a Demon Internet host in
1860 multidrop mode, and use the *ENV extension to get an envelope To
1863 <p>The autodetection works by looking at the hostname in the POP3
1864 greeting line; if you're accessing Demon Internet through a proxy
1865 it may fail. To force SDPS mode, pick "sdps" as your protocol.</p>
1867 <h2><a id="I3" name="I3">I3. How can I use fetchmail with usa.net's
1870 <p>Enable '<code>fetchall</code>'. A user reports that the 2.2
1871 version of USA.NET's POP server reports that you must use the
1872 '<code>fetchall</code>' option to make sure that all of the mail is
1873 retrieved, otherwise some may be left on the server. This is almost
1874 certainly a server bug.</p>
1876 <p>The usa.net servers (at least in their 2.2 version, June 1998)
1877 don't handle the TOP command properly, either. Regardless of the
1878 argument you give it, they retrieve only about 10 lines of the
1879 message. Fetchmail normally uses TOP for message retrieval in order
1880 to avoid marking messages seen, but '<code>fetchall</code>' forces
1881 it to use RETR instead.</p>
1883 <p>Also, we're told USA.NET adds a ton of hops to your messages.
1884 You may need to raise the MaxHopCount parameter in your sendmail.cf
1885 to avoid having fetched mail rejected.</p>
1887 <h2><a id="I4" name="I4">I4. How can I use fetchmail with geocities
1888 POP3 servers?</a></h2>
1890 <p>Nathan Cutler reports that the the mail.geocities.com POP3
1891 servers fail to include the first Received line of the message in
1892 the send to fetchmail. This can solve problems if your MUA
1893 interprets Received continuations as body lines and doesn't parse
1894 any of the following headers.</p>
1896 <p>Workaround is to use "mda" keyword or "--mda" switch:</p>
1899 mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
1902 <p>Replace \t with exactly one tabulation character.</p>
1904 <p>You should also consider using "fetchall" option because
1905 Geocities' servers sometimes think that the first 45 messages have
1906 already been read.</p>
1908 <h2><a id="I5" name="I5">I5. How can I use fetchmail with Hotmail or Lycos Webmail?</a></h2>
1910 <p>You can't directly. But you can use fetchmail with hotmail or lycos
1911 webmail with the help of the <a
1912 href='http://people.freenet.de/courierdave/'>HotWayDaemon</a>
1913 daemon. You don't even need to install hotwayd as a daemon in
1914 <samp>inetd.conf</samp> but can use it as a plugin. Your
1915 configuration should look like this:</p>
1918 poll localhost protocol pop3 tracepolls
1919 plugin "/usr/local/sbin/hotwayd -l 0 -p yourproxy:yourproxyport"
1920 username "youremail@hotmail.com" password "yourpassword"
1924 <p>As a second option you may consider using <a
1925 href="http://linux.cudeso.be/linuxdoc/gotmail.php">gotmail</a>.</p>
1927 <h2><a id="I6" name="I6">I6. How can I use fetchmail with MSN?</a></h2>
1929 <p>You can't. MSN uses something that looks like POP3, except the
1930 authentication part is nonstandard. And of course they don't
1931 document it, so nobody but their Windows clients can speak it.</p>
1933 <p>This is a customer lock-in tactic; we recommend boycotting MSN
1934 as the only appropriate response.</p>
1936 <p>As of 5.0.8, we have support for the client side of NTLM
1937 authentication. It's possible this may enable fetchmail to talk to
1938 MSN; if so, somebody should report it so this FAQ can be
1941 <h2><a id="I7" name="I7">I7. How can I use fetchmail with SpryNet?</a></h2>
1943 <p>The SpryNet POP3 servers mark a message queried with TOP as
1944 seen. This means that if your connection drops in mid-message, it
1945 may end up invisibly stuck on your mail spool. Use the
1946 <code>fetchall</code> flag to ensure that it's recovered on the
1949 <h2><a id="I8" name="I8">I8. How can I use fetchmail with comcast.net or
1950 other Maillennium servers?</a></h2>
1952 <p>Stock fetchmail will work with a
1953 Maillennium POP3/PROXY server... <em>but</em> this server will
1954 truncate "TOP" responses after 64 - 82 kB (we have varying reports),
1955 in violation of Internet Standard #53 aka. RFC-1939 (POP3). Don't
1956 mistake this for a fetchmail bug. (Reported July 2003.) Comcast
1957 documented they haven't understood what this is about in <a
1958 href="http://lists.ccil.org/pipermail/fetchmail-friends/2004-April/008523.html">two
1959 messages from April 2004.</a></p>
1961 <p>Beginning with version 6.3.2, fetchmail will fall back to the RETR
1962 command if the greeting string contains "Maillennium POP3/PROXY server",
1963 and print a warning message. This means however that fetchmail has no
1964 means to prevent the "seen" flag from being set on the server (Note that
1965 officially, POP3 has no notion of seen tracking, but it works for some
1968 <p>Workaround for older versions: use the <tt>fetchall</tt> option.</p>
1971 <h1>How to set up well-known security and authentication
1973 <h2><a id="K1" name="K1">K1. How can I use fetchmail with SOCKS?</a></h2>
1975 <p>Giuseppe Guerini added a <kbd>--with-socks</kbd> compile-time option
1976 that supports linking with socks library. If you specify the value of
1977 this option as "yes", the configure script will try to find the Rconnect
1978 library and set the makefile up to link it. You can also specify a
1979 directory containing the Rconnect library.</p>
1981 <p>Alan Schmitt has added a similar <kbd>--with-socks5</kbd> option that may
1982 work better if you have a recent version of the SOCKS library.</p>
1984 <p>In either case, fetchmail has no direct configuration hooks, but you
1985 can specify which socks configuration file the library should read by
1986 means of the <tt>SOCKS_CONF</tt> environment variable. In order to
1987 bypass the SOCKS proxy altogether, you could run (adding your usual
1988 options to the end of this line):</p>
1990 <pre>env SOCKS_CONF=/dev/null fetchmail</pre>
1992 <h2><a id="K2" name="K2">K2. How can I use fetchmail with IPv6 and
1995 <p>To use fetchmail with IPv6, you need a system that supports
1996 IPv6, the "Basic Socket Interface Extensions for IPv6" (RFC 2133).
1999 <p>The NRL IPv6+IPsec software distribution can be obtained from:
2001 href="http://web.mit.edu/network/isakmp/">http://web.mit.edu/network/isakmp/</a></p>
2003 <p>More information on using IPv6 with Linux can be obtained
2008 href="http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html">
2009 http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html</a></li>
2012 <h2><a id="K3" name="K3">K3. How can I get fetchmail to work with
2015 <p>Use the <tt>plugin</tt> option. This is dead simple with
2019 plugin "ssh %h /usr/sbin/imapd"
2022 <p>You may have to use a different absolute pathname, whatever the
2023 location of imapd on your mailserver is. This option tells
2024 fetchmail that instead of opening a connection on the server's port
2025 143 and doing standard IMAP authentication, fetchmail should ssh to
2026 the server and run imapd, using the more secure ssh authentication
2027 (as well as getting ssh's end-to-end encryption). Most IMAP daemons
2028 will detect that they've been called from the command line and
2029 assume the connection is preauthenticated.</p>
2031 <p>POP3 daemons aren't quite as smart. They won't know they are
2032 preauthenticated in this mode, so you'll actually have to ship your
2033 password. It will be under ssh encryption, though, so that
2034 shouldn't be a problem.</p>
2036 <h2><a id="K4" name="K4">K4. What do I have to do to use the
2037 IMAP-GSS protocol?</a></h2>
2039 <p>Fetchmail can use RFC1731 GSSAPI authorization to safely
2040 identify you to your IMAP server, as long as you can share
2041 Kerberos V credentials with your mail host and you have a GSSAPI-capable
2042 IMAP server - those are few.</p>
2044 <p>fetchmail does not compile in support for GSS by
2045 default, since it requires libraries from the Kerberos V
2046 distribution (available via FTP at <a
2047 href="ftp://athena-dist.mit.edu/pub/ATHENA/kerberos">athena-dist.mit.edu</a>).
2048 If you have these, compiling in GSS support is simple: add a
2049 <code>--with-gssapi=[/path/to/krb5/root]</code> option to
2050 configure. For instance, I have all of my Kerberos V libraries
2051 installed under /usr/krb5 so I run <code>configure
2052 --with-gssapi=/usr/krb5</code></p>
2054 <p>Setting up Kerberos V authentication is beyond the scope of this
2055 FAQ (you may find Jim Rome's paper <a
2056 href="http://www.ornl.gov/~jar/HowToKerb.html">How to Kerberize
2057 your site</a> helpful), but you'll at least need to add a
2058 credential for imap/[mailhost] to the keytab of the mail server
2059 (IMAP doesn't just use the host key). Then you'll need to have your
2060 credentials ready on your machine (cf. kinit).</p>
2062 <p>After that things are very simple. Set your protocol to imap-gss
2063 in your .fetchmailrc, and omit the password, since imap-gss doesn't
2064 need one. You can specify a username if you want, but this is only
2065 useful if your mailbox belongs to a username different from your
2066 Kerberos principal.</p>
2068 <p>Now you don't have to worry about your password appearing in
2069 cleartext in your .fetchmailrc, or across the network.</p>
2071 <h2><a id="K5" name="K5">K5. How can I use fetchmail with
2074 <p>You'll need to have the <a
2075 href="http://www.openssl.org/">OpenSSL</a> libraries installed, and they
2076 should at least be version 0.9.6.
2077 Configure with --with-ssl. If you have the OpenSSL libraries
2078 installed in the default location (/usr/local/ssl) ths will
2079 suffice. If you have them installed in a non-default location,
2080 you'll need to specify it as an argument to --with-ssl after an
2083 <p>Fetchmail binaries built this way support <code>ssl</code>,
2084 <code>sslkey</code>, and <code>sslcert</code> options that control
2085 SSL encryption, and will automatically use <code>tls</code> if the
2086 server offers it. You will need to have an SSL-enabled mailserver to
2087 use these options. See the manual page for details and some words
2088 of care on the limited security provided.</p>
2090 <p>If your open OpenSSL session dies with a message that complains
2091 "PRNG not seeded", update or improve your operating system. This
2092 means that the OpenSSL library on your machine has been unable to
2093 locate a source of random bits from which to seed its random-number
2094 generator; normally these come from the <tt>/dev/urandom</tt>, and
2095 this message probably means your OS doesn't have that device.</p>
2097 <p>An interactive program could seed the random number generator
2098 from keystroke timings or some other form of user input. Because
2099 fetchmail is primarily designed to run forever as a background
2100 daemon, that option is not available in this case.</p>
2102 <p>If you don't have the libraries installed, but do have the
2103 OpenSSL utility toolkit, something like this may work (but will not
2104 authenticate the server):</p>
2107 poll MYSERVER port 993 plugin "openssl s_client -connect %h:%p"
2108 protocol imap username MYUSERNAME password MYPASSWORD
2111 <p>You should note that SSL is only secure against a "man-in-the-middle"
2112 attack if the client is able to verify that the peer's public key is the
2113 correct one, and has not been substituted by an attacker. fetchmail can do
2114 this in one of two ways: by verifying the SSL certificate, or by checking
2115 the fingerprint of the peer's public key.</p>
2117 <p>There are three parts to SSL certificate verification: checking that the
2118 domain name in the certificate matches the hostname you asked to connect to;
2119 checking that the certificate expiry date has not passed; and checking that
2120 the certificate has been signed by a known Certificate Authority (CA). This
2121 last step takes some preparation, as you need to install the root
2122 certificates of all the CA's which you might come across.</p>
2124 <p>The easiest way to do this is using the root CA keys supplied in the
2125 OpenSSL distribution, which means you need to download and unpack the
2126 source tarball from www.openssl.org. Once you have done that:</p>
2129 <li><code>mkdir /etc/ssl/certs</code></li>
2130 <li>in the openssl-x.x.x/certs directory: <code>cp *.pem /etc/ssl/certs/</code></li>
2131 <li>in the openssl-x.x.x/tools directory: edit c_rehash and set
2132 <code>$dir="/etc/ssl"</code></li>
2133 <li>run "perl c_rehash". This generates a number of symlinks within the
2134 /etc/ssl/certs/ directory</li>
2137 <p>Now in .fetchmailrc, set option sslcertpath to point to this
2141 poll pop3.example.com proto pop3 uidl no dns
2142 user foobar@example.com password xyzzy is foobar ssl sslcertpath /etc/ssl/certs
2145 <p>If the server certificate has not been signed by a known CA (e.g. it is a
2146 self-signed certificate), then this certificate validation will always
2149 <p>Certificate verification is always attempted. If it fails, by default a
2150 warning is printed but the connection carries on (which means you are not
2151 protected against attack). If your server's certificate has been properly
2152 set up and verifies correctly, then add the "sslcertck" option to enforce
2153 validation. If your server doesn't have a valid certificate though (e.g. it
2154 has a self-signed certificate) then it will never verify, and the only way
2155 you can protect yourself is by checking the fingerprint.</p>
2157 <p>To check the peer fingerprint: first use fetchmail -v once to connect to
2158 the host, at a time when you are pretty sure that there is no attack in
2159 progress (e.g. you are not traversing any untrusted network to reach the
2160 server). Make a note of the fingerprint shown. Now embed this in your
2161 .fetchmailrc using the sslfingerprint option: e.g.</p>
2164 poll pop3.example.com proto pop3 uidl no dns
2165 user foobar@example.com password xyzzy is foobar
2166 ssl sslfingerprint "67:3E:02:94:D3:5B:C3:16:86:71:37:01:B1:3B:BC:E2"
2169 <p>When you next connect, the public key presented by the server will be
2170 verified against the fingerprint given. If it's different, it may mean that
2171 a man-in-the-middle attack is in progress - or it might just mean that the
2172 server changed its key. It's up to you to determine which has happened.</p>
2174 <h2><a id="K6" name="K6">K6. How can I tell fetchmail not to use TLS
2175 if the server advertises it? Why does fetchmail use SSL even
2176 though not configured?</a></h2>
2178 <p>Some servers advertise STLS (POP3) or STARTTLS (IMAP), and fetchmail
2179 will automatically attempt TLS negotiation if SSL was enabled at compile
2180 time. This can however cause problems if the upstream didn't configure
2181 his certificates properly.</p>
2183 <p>In order to prevent fetchmail from trying TLS (STLS, STARTTLS)
2184 negotiation, add this option:</p>
2186 <pre>sslproto ssl23</pre>
2188 <p>This restricts fetchmail's SSL/TLS protocol choice from the default
2189 "SSLv2, SSLv3, TLSv1" to the two SSL variants, disabling TLSv1. Note
2190 however that this causes the connection to be unencrypted unless an
2191 encrypting "plugin" is used or SSL is requested explicitly.</p>
2194 <h1>Runtime fatal errors</h1>
2195 <h2><a id="R1" name="R1">R1. Fetchmail isn't working, and -v shows
2196 'SMTP connect failed' messages.</a></h2>
2198 <p>Fetchmail itself is probably working, but your SMTP port 25
2199 listener is down or inaccessible.</p>
2201 <p>The first thing to check is if you can telnet to port 25 on your
2202 smtp host (which is normally 'localhost' unless you've specified an
2203 smtp option in your .fetchmailrc or on the command line) and get a
2204 greeting line from the listener. If the SMTP host is inaccessible
2205 or the listener is down, fix that first.</p>
2207 <p>In Red Hat Linux 6.x, SMTP is disabled by default. To fix this,
2208 set "DAEMON=yes" in your /etc/sysconfig/sendmail file, then restart
2209 sendmail by running "/sbin/service sendmail restart".</p>
2211 <p>If the listener seems to be up when you test with telnet, the
2212 most benign and typical problem is that the listener had a
2213 momentary seizure due to resource exhaustion while fetchmail was
2214 polling it -- process table full or some other problem that stopped
2215 the listener process from forking. If your SMTP host is not
2216 'localhost' or something else in /etc/hosts, the fetchmail glitch
2217 could also have been caused by transient nameserver failure.</p>
2219 <p>Try running fetchmail -v again; if it succeeds, you had one of
2220 these kinds of transient glitch. You can ignore these hiccups,
2221 because a future fetchmail run will get the mail through.</p>
2223 <p>If the listener tests up, but you have chronic failures trying
2224 to connect to it anyway, your problem is more serious. One way to
2225 work around chronic SMTP connect problems is to use --mda. But this
2226 only attacks the symptom; you may have a DNS or TCP routing
2227 problem. You should really try to figure out what's going on
2228 underneath before it bites you some other way.</p>
2230 <p>We have one report (from toby@eskimo.com) that you can sometimes
2231 solve such problems by doing an <code>smtp</code> declaration with
2232 an IP address that your routing table maps to something other than
2233 the loopback device (he used ppp0).</p>
2235 <p>We also have a report that this error can be caused by having an
2236 /etc/hosts file that associates your client host name with more
2237 than one IP address.</p>
2239 <p>It's also possible that your DNS configuration isn't looking at
2240 <code>/etc/hosts</code> at all. If you're using libc5, look at
2241 <code>/etc/resolv.conf</code>; it should say something like:</p>
2247 <p>so your <code>/etc/hosts</code> file is checked first. If you're
2248 running GNU libc6, check your <code>/etc/nsswitch.conf</code> file.
2249 Make sure it says something like</p>
2255 <p>again, in order to make sure <code>/etc/hosts</code> is seen
2258 <p>If you have a hostname set for your machine, and this hostname
2259 does not appear in /etc/hosts, you will be able to telnet to port
2260 25 and even send a mail with rcpt to: user@host-not-in-/etc/hosts,
2261 but fetchmail can't seem to get in touch with sendmail, no matter
2262 what you set smtpaddress to.</p>
2264 <p>We had another report from a Linux user of fetchmail 2.1 who
2265 solved his SMTP connection problem by removing the reference to
2266 -lresolv from his link line and relinking. Apparently in some older
2267 Linux distributions the libc bind library version works better.</p>
2269 <p>As of 2.2, the configure script has been hacked so the bind
2270 library is linked only if it is actually needed. So under Linux it
2271 won't be, and this particular cause should go away.</p>
2273 <h2><a id="R2" name="R2">R2. When I try to configure an MDA,
2274 fetchmail doesn't work.</a></h2>
2276 <p>(I hear this one from people who have run into the blank-line
2277 problem in <a href="#X1">X1</a>.)</p>
2279 <p>Try sending yourself test mail and retrieving it using the
2280 command-line options '<code>-k -m cat</code>'. This will dump
2281 exactly what fetchmail retrieves to standard output (plus the
2282 Received line fetchmail itself adds to the headers).</p>
2284 <p>If the dump doesn't match what shows up in your mailbox when you
2285 configure an MDA, your MDA is mangling the message. If it doesn't
2286 match what you sent, then fetchmail or something on the server is
2289 <h2><a id="R3" name="R3">R3. Fetchmail dumps core when given an
2290 invalid rc file.</a></h2>
2292 <p>Note that this bug should no longer occur when using prepackaged
2293 fetchmail versions or installing unmodified original tarballs, since
2294 these ship with a proper parser .c file.</p>
2296 <p>This is usually reported from AIX or Ultrix, but has even been
2297 known to happen on Linuxes without a recent version of
2298 <code>flex</code> installed. The problem appears to be a result of
2299 building with an archaic version of lex.</p>
2301 <p>Workaround: fix the syntax of your .fetchmailrc file.</p>
2303 <p>Fix: build and install the latest version of <a
2304 href="http://flex.sourceforge.net/">flex</a>.</p>
2306 <h2><a id="R4" name="R4"><strike>R4. Fetchmail dumps core in -V mode, but
2307 operates normally otherwise.</strike></a></h2>
2309 <p><em>The information that used to be here referred to bugs in Linux libc5
2310 systems, which are deemed obsolete by now.</em></p>
2312 <h2><a id="R5" name="R5">R5. Running fetchmail in daemon mode
2313 doesn't work.</a><br/>
2316 <p>We have one report from a SunOS 4.1.4 user that trying to run
2317 fetchmail in detached daemon mode doesn't work, but that using the
2318 same options with -N (nodetach) is OK. We have another report of
2319 similar behavior from one Linux user, but many other Linux users
2320 report no problem.</p>
2322 <p>If this happens, you have a specific portability problem with
2323 the code in daemon.c that detaches and backgrounds the daemon
2324 fetchmail. The isolated Linux case has been chased down to a
2325 failure in dup(2) that may reflect a glibc bug.</p>
2327 <p>As a workaround, you can start fetchmail with -N and an
2328 ampersand to background it. A Sun user recommends this:</p>
2331 (fetchmail --nodetach <other params> &)
2334 <p>The extra pair of parens is significant --- it makes sure that
2335 the process detaches from the initial shell (one more shell is
2336 started and dies immediately, detaching fetchmail and making it
2337 child of PID 1). This is important when you start fetchmail
2338 interactively and than quit interactive shell. The line above makes
2339 sure fetchmail lives after that!</p>
2341 <h2><a id="R6" name="R6">R6. Fetchmail randomly dies with socket
2344 <p>Check the MTU value in your PPP interface reported by
2345 <code>/sbin/ifconfig</code>. If it's over 600, change it in your
2346 PPP options file. (<code>/etc/ppp/options</code> on my box). Here
2347 are option values that work:</p>
2354 <p>Another circumstance that can trigger this is if you are polling
2355 a virtual-mail-server name that is round-robin connected to
2356 different actual servers, so you get different IP addresses on
2357 different poll cycles. To work around this, change the poll name
2358 either to the real name of one of the servers in the ring or to a
2359 corresponding IP address.</p>
2361 <h2><a id="R7" name="R7">R7. Fetchmail running as root stopped
2362 working after an OS upgrade</a></h2>
2364 <p>In RH 6.0, the HOME value in the boot-time root environment
2365 changed from /root to / as the result of a change in init. Move
2366 your .fetchmailrc or use a -f option to explicitly point at the
2367 file. (Oddly, a similar problem has been reported from Debian
2370 <h2><a id="R8" name="R8">R8. Fetchmail is timing out after fetching
2371 certain messages but before deleting them</a></h2>
2373 <p>There's a TCP/IP stalling problem under Redhat 6.0 (and possibly
2374 other recent Linuxes) that can cause this symptom. Brian Boutel
2378 <p>TCP timestamps are turned on on my Linux boxes (I assume it's
2379 now the default). This uses 12 extra bytes per segment. When the
2380 tcp connection starts, the other end agrees a MSS of 1460, and then
2381 fragments 1460 byte chunks into 1448 and 12, because is is not
2382 allowing for the timestamp.</p>
2384 <p>Then, for reasons I can't explain, it waits a long time
2385 (typically 2 minutes) after the ack is sent before sending the next
2386 (fragmented) packet. Turning off tcp timestamps avoids the
2387 fragmentation and restores normal behaviour. To do this,
2390 <p>echo 0 > /proc/sys/net/ipv4/tcp_timestamps</p>
2392 <p>I'm still unclear about the details of why this is happening. At
2393 least [now] I am now getting good performance and no queue
2397 <h2><a id="R9" name="R9">R9. Fetchmail is timing out during message
2400 <p>This is probably a general networking issue. Sending a "RETR"
2401 command will cause the server to start sending large amounts of
2402 data, which means large packets. If your networking layer has a
2403 packet-fragmentation problem or improper firewall settings break Path
2404 MTU discovery (when for instance all ICMP traffic is blocked), that's
2405 where you'll see it.</p>
2407 <h2><a id="R10" name="R10"><strike>R10. Fetchmail is dying with
2408 SIGPIPE.</strike></a></h2>
2410 <p><em>Fetchmail 6.3.5 and newer block SIGPIPE, and many older versions have
2411 already handled this signal, so you shouldn't be seeing SIGPIPE
2414 <h2><a id="R11" name="R11">R11. My server is hanging or emitting
2415 errors on CAPA.</a></h2>
2417 <p>Your POP3 server is broken. You can work around this with the
2418 declaration <tt>auth password</tt> in your .fetchmailrc.</p>
2420 <h2><a id="R12" name="R12">R12. Fetchmail isn't working and reports
2421 getaddrinfo errors.</a></h2>
2422 <ol><li>Make sure you haven't mistyped the host name or address, and that
2423 your DNS is working. If you cannot fix DNS, give the numeric host
2424 literal, for instance, 192.168.0.1</li>
2425 <li>Make sure your <code>/etc/services</code> file (or other
2426 services database) contains the necessary service entries. If you
2427 cannot fix the services database, use the --service option and give the
2428 numeric port address. Common port addresses are:<table
2429 summary="Common port addresses for IMAP, POP3 and their SSL
2431 <tr><th>service</th><th>port</th></tr>
2432 <tr><td>IMAP</td><td>143</td></tr>
2433 <tr><td>IMAP+SSL</td><td>993</td></tr>
2434 <tr><td>POP3</td><td>110</td></tr>
2435 <tr><td>POP3+SSL</td><td>995</td></tr>
2438 <h2><a id="R13" name="R13">R13. What does "Interrupted system call"
2441 <p>Non-fatal signals (such as timers set by fetchmail itself) can
2442 interrupt long-running functions and will then be reported as
2443 "Interrupted system call". These can sometimes be timeouts.</p>
2446 <h1>Hangs and lockups</h1>
2447 <h2><a id="H1" name="H1">H1. Fetchmail hangs when used with
2450 <p>Your problem may be with pppd's 'demand' option. We have a
2451 report that fetchmail doesn't play well with it, but works with
2452 pppd if 'demand' is turned off. We have no idea why this is.</p>
2454 <h2><a id="H2" name="H2">H2. Fetchmail hangs during the MAIL FROM
2457 <p>The symptom: 'fetchmail -v' retrieves mail fine, but appears to
2458 hang after sending the MAIL FROM command</p>
2461 SMTP> MAIL FROM: <someone@somewhere>
2464 <p>The hang is actually occuring when sendmail looks up a sender's
2465 address in DNS. The problem isn't in fetchmail but in the
2466 configuration of sendmail. You must enable the 'nodns' and
2467 'nocanonify' features of sendmail.</p>
2469 <p>Here was my fix for RedHat 7.2:</p>
2472 <li># cd /etc/mail</li>
2474 <li># cp sendmail.mc sendmail-mine.mc</li>
2476 <li>Edit sendmail-mine.mc and add lines:
2484 <li>Build a new sendmail.cf
2487 # m4 sendmail-mine.cf > /etc/sendmail.cf
2491 <li>Restart sendmail.</li>
2494 <p>For more details consult the file
2495 /usr/share/sendmail-cf/README.</p>
2497 <h2><a id="H3" name="H3">H3. Fetchmail hangs while fetching
2500 <p>The symption: 'fetchmail -v' retrieves the first few messages,
2501 but hangs returning:</p>
2504 fetchmail: SMTP< 550 5.0.0 Access denied
2505 fetchmail: SMTP> RSET
2506 fetchmail: SMTP< 250 2.0.0 Reset state
2507 .......fetchmail: flushed
2508 fetchmail: POP3> DELE 1
2509 fetchmail: POP3< +OK marked deleted
2512 <p>Check and see if you're allowing sendmail connections through
2515 <p>Adding 'sendmail : 127.0.0.1' to /etc/hosts.allow could solve
2519 <h1>Disappearing mail</h1>
2520 <h2><a id="D1" name="D1">D1. I think I've set up fetchmail
2521 correctly, but I'm not getting any mail.</a></h2>
2523 <p>Maybe you have a .forward or alias set up that you've forgotten
2524 about. You should probably remove it.</p>
2526 <p>Or maybe you're trying to run fetchmail in multidrop mode as
2527 root without a .fetchmailrc file. This doesn't do what you think it
2528 should; see question <a href="#C1">C1</a>.</p>
2530 <p>Or you may not be connecting to the SMTP listener. Run fetchmail
2531 -v and see <a href="#R1">R1</a>.</p>
2533 <p>Or you may have your local user set incorrectly. In the
2537 user 'remoteuser' there with password '*' is 'localuser' here
2540 <p>make sure that 'localuser' does exist and can receive mail.</p>
2542 <h2><a id="D2" name="D2">D2. All my mail seems to disappear after a
2543 dropped connection.</a></h2>
2545 <p>One POP3 daemon used in the Berkeley Unix world that reports
2546 itself as POP3 version 1.004 actually throws the queue away. 1.005
2547 fixed that. If you're running this one, upgrade immediately. (It
2548 also truncates long lines at column 1024.)</p>
2550 <p>Many POP servers, if an interruption occurs, will restore the
2551 whole mail queue after about 10 minutes. Better ones will restore it
2552 right away. If you have an interruption and don't see it right
2553 away, cross your fingers and wait ten minutes before retrying.</p>
2555 <p>Good servers are designed to restore the entire queue, including
2556 messages you have deleted. If you have one of these and it flakes out on
2557 you a lot, try setting a small <code>--fetchlimit</code> value. This
2558 will result in more IP connects to the server, but will mean it actually
2559 executes changes to the queue more often.</p>
2561 <h2><a id="D3" name="D3">D3. Mail that was being fetched when I
2562 interrupted my fetchmail seems to have been vanished.</a></h2>
2564 <p>Fetchmail only sends a delete mail request to the server when
2565 either (a) it gets a positive delivery acknowledgment from the SMTP
2566 listener, or (b) it gets one of the spam-filter errors (see the
2567 description of the <code>antispam></code> option) from the
2568 listener. No interrupt can cause it to lose mail.</p>
2570 <p>However, IMAP2bis has a design problem in that its normal fetch
2571 command marks a message 'seen' as soon as the fetch command to get
2572 it is sent down. If for some reason the message isn't actually
2573 delivered (you take a line hit during the download, or your port 25
2574 listener can't find enough free disk space, or you interrupt the
2575 delivery in mid-message) that 'seen' message can lurk invisibly in
2576 your server mailbox forever.</p>
2578 <p>Workaround: add the '<code>fetchall</code>' keyword to your
2581 <p>Solution: switch to an <a href="http://www.imap.org/">IMAP4</a>
2585 <h1>Multidrop-mode problems</h1>
2586 <h2><a id="M1" name="M1">M1. I've declared local names, but all my
2587 multidrop mail is going to root anyway.</a></h2>
2589 <p>Somehow your fetchmail is never recognizing the hostname part of
2590 recipient names it parses out of Envelope-header lines (or these are
2591 improperly configured) as
2592 matching a name within the designated domains. To check this, run
2593 fetchmail in foreground with -v -v on. You will probably see a lot
2594 of messages with the format "line rejected, %s is not an alias of
2595 the mailserver" or "no address matches; forwarding to %s."</p>
2597 <p>These errors usually indicate some kind of configuration
2600 <p>The easiest workaround is to add a '<code>via</code>' option (if
2601 necessary) and add enough '<code>aka</code>' declarations to cover all
2602 of your mailserver's aliases, then say '<code>no dns</code>'. This will
2603 take DNS out of the picture (though it means mail may be uncollected if
2604 it's sent to an alias of the mailserver that you don't have listed).</p>
2606 <p>Occasionally these errors indicate the sort of header-parsing
2607 problem described in <a href="#M7">M7</a>.</p>
2609 <h2><a id="M2" name="M2">M2. I can't seem to get fetchmail to route
2610 to a local domain properly.</a></h2>
2612 <p>A lot of people want to use fetchmail as a poor man's
2613 internetwork mail gateway, picking up mail accumulated for a whole
2614 domain in a single server mailbox and then routing based on what's
2615 in the To/Cc/Bcc lines.</p>
2617 <p>In general, this is not really a good idea. It would be smarter
2618 to just let the mail sit in the mailserver's queue and use
2619 fetchmail's ETRN or ODMR modes to trigger SMTP sends periodically
2620 (of course, this means you have to poll more frequently than the
2621 mailserver's expiration period). If you can't arrange this, try
2622 setting up a UUCP feed.</p>
2624 <p>If neither of these alternatives is available, multidrop mode
2625 may do (though you <em>are</em> going to get hurt by some mailing
2626 list software; see the caveats under THE USE AND ABUSE OF MULTIDROP
2627 MAILBOXES on the man page, and check what is needed at <a
2628 href="http://home.pages.de/~mandree/mail/multidrop">Matthias
2629 Andree's "Requisites for working multidrop
2630 mailboxes"</a>). If you want to try it, the way to do it is
2631 with the '<code>localdomains</code>' option.</p>
2633 <p>In general, if you use localdomains you need to make sure of two
2636 <p><strong>1. You've actually set up your .fetchmailrc entry to
2637 invoke multidrop mode.</strong></p>
2639 <p>Many people set a '<code>localdomains</code>' list and then
2640 forget that fetchmail wants to see more than one name (or the
2641 wildcard '*') in a '<code>here</code>' list before it will do
2642 multidrop routing.</p>
2644 <p><strong>2. You may have to set 'no envelope'.</strong></p>
2646 <p>Normally, multidrop mode tries to deduce an envelope address
2647 from a message before parsing the To/Cc/Bcc lines (this enables it
2648 to avoid losing to mailing list software that doesn't put a
2649 recipient address in the To lines).</p>
2651 <p>Some ways of accumulating a whole domain's messages in a single
2652 server mailbox mean it all ends up with a single envelope address
2653 that is useless for rerouting purposes. In this particular case, sell
2654 your ISP a clue. If that does not work, you may have to set
2655 '<code>no envelope</code>' to prevent fetchmail from being
2656 bamboozled by this, but a missing envelope makes multidrop routing
2659 <p>Check also answer <a href="#T1">T1</a> on a reliable way to do
2660 multidrop delivery if your ISP (or your mail redirection provider)
2663 <h2><a id="M3" name="M3">M3. I tried to run a mailing list using
2664 multidrop, and I have a mail loop!</a></h2>
2666 <p>This isn't fetchmail's fault. Check your mailing list. If the
2667 list expansion includes yourself or anybody else at your mailserver
2668 (that is, not on the client side) you've created a mail loop. Just
2669 chop the host part off any local addresses in the list.</p>
2671 <p>If you use sendmail, you can check the list expansion with
2672 <code>sendmail -bv</code>.</p>
2674 <h2><a id="M4" name="M4"><strike>M4. My multidrop fetchmail seems to be
2675 having DNS problems.</strike></a></h2>
2677 <p>The answer that used to be here no longer applies to fetchmail.</p>
2679 <h2><a id="M5" name="M5">M5. I'm seeing long DNS delays before each
2680 message is processed.</a></h2>
2682 <p>Use the '<code>aka</code>' option to pre-declare as many of your
2683 mailserver's DNS names as you can. When an address's host part
2684 matches an aka name, no DNS lookup needs to be done to check
2687 <p>If you're sure you've pre-declared all of your mailserver's DNS
2688 names, you can use the '<code>no dns</code>' option to prevent
2689 other hostname parts from being looked up at all.</p>
2691 <p>Sometimes delays are unavoidable. Some SMTP listeners try to
2692 call DNS on the From-address hostname as a way of checking that the
2693 address is valid.</p>
2695 <h2><a id="M6" name="M6">M6. How do I get multidrop mode to work
2696 with majordomo?</a></h2>
2698 <p>In order for sendmail to execute the command strings in the
2699 majordomo alias file, it is necessary for sendmail to think that
2700 the mail it receives via SMTP really is destined for a local user
2701 name. A normal virtual-domain setup results in delivery to the
2702 default mailbox, rather than expansion through majordomo.</p>
2704 <p>Michael <michael@bizsystems.com> gave us a recipe for
2705 dealing with this case that pairs a run control file like this:</p>
2708 poll your.pop3.server proto pop3:
2710 localdomains virtual.localdomain1.com virtual.localdomain2.com ...
2711 user yourISPusername is root * here,
2712 password yourISPpassword fetchall
2715 <p>with a hack on your local sendmail.cf like this:</p>
2718 #############################################
2719 # virtual info, local hack for ruleset 98 #
2720 #############################################
2722 # domains to treat as direct mapped local domain
2724 CVvirtual.localdomain1.com virtual.localdomain2.com ...
2725 ---------------------------
2727 -------------------------
2728 # handle virtual users
2730 R$+ <@ $=V . > $: $1 < @ $j . >
2731 R< @ > $+ < @ $=V . > $: $1 < @ $j . >
2732 R< @ > $+ $: $1
2733 R< error : $- $+ > $* $#error $@ $1 $: $2
2734 R< $+ > $+ < @ $+ > $: $>97 $1
2737 <p>This ruleset just strips virtual domain names off the addresses
2738 of incoming mail. Your sendmail must be 8.8 or newer for this to
2739 work. Michael says:</p>
2741 <blockquote>I use this scheme with 2 virtual domains and the
2742 default ISP user+domain and service about 30 mail accounts +
2743 majordomo on my inside pop3 server with fetchmail and sendmail
2746 <h2><a id="M7" name="M7">M7. Multidrop mode isn't parsing envelope
2747 addresses from my Received headers as it should.</a></h2>
2749 <p>It may happen that you're getting what appear to be well-formed
2750 sendmail Received headers, but fetchmail can't seem to extract an
2751 envelope address from them. There can be a couple of reasons for
2754 <h3>Spurious Received lines need to be skipped:</h3>
2756 <p>First, fetchmail might be looking at the wrong Received header.
2757 Normally it looks only on the first one it sees, on the theory that
2758 that one was last added and is going to be the one containing your
2759 mailserver's theory of who the message was addressed to.</p>
2761 <p>Some (unusual) mailserver configurations will generate extra
2762 Received lines which you need to skip. To arrange this, use the
2763 optional skip prefix argument of the 'envelope' option; you may
2764 need to say something like '<code>envelope 1 Received</code>' or
2765 '<code>envelope 2 Received</code>'.</p>
2767 <h3>The 'by' clause doesn't contain a mailserver alias:</h3>
2769 <p>When fetchmail parses a Received line that looks like</p>
2772 Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
2773 by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
2774 for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
2777 <p>it checks to see if 'iserv.ttns.net' is a DNS alias of your
2778 mailserver before accepting 'ksturgeon@fbceg.org' as an envelope
2779 address. This check might fail if your DNS were misconfigured, or
2780 if you were using 'no dns' and had failed to declare iserv.ttns.net
2781 as an alias of your server.</p>
2783 <h2><a id="M8" name="M8">M8. Users are getting multiple copies of
2786 <p>It's a consequence of multidrop. What's happening is that you
2787 have N users subscribed to the same list. The list software sends N
2788 copies, not knowing they will end up in the same multidrop box.
2789 Since they are both locally addressed to all N users, fetchmail
2790 delivers N copies to each user.</p>
2792 <p>Fetchmail tries to eliminate adjacent duplicate messages in a
2793 multidrop mailbox. However, this logic depends on the message-ID
2794 being identical in both copies. It also depends on the two copies
2795 being adjacent in the server mailbox. The former is usually the
2796 case, but the latter condition sometimes fails in a
2797 timing-dependent way if the server was processing multiple incoming
2800 <p>I could eliminate this problem by keeping a list of all
2801 message-IDs received during a poll so far and dropping any message
2802 that matches a seen mail ID. The trouble is that this is an O(N**2)
2803 operation that might significantly slow down the retrieval of large
2806 <p>The real solution however is to make sure that fetchmail can find the
2807 envelope recipient properly, which will reliably prevent this message
2811 <h1>Mangled mail</h1>
2812 <h2><a id="X1" name="X1">X1. Spurious blank lines are appearing in
2813 the headers of fetched mail.</a></h2>
2815 <p>What's probably happening is that the POP/IMAP daemon on your
2816 mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
2817 something in your delivery path (most likely an old version of the
2818 <em>deliver</em> program, which sendmail often calls to do local
2819 delivery) is failing to recognize it as a header.</p>
2821 <p>This is not fetchmail's problem. The first thing to try is
2822 installing a current version of <em>deliver</em>. If this doesn't
2823 work, try to figure out which other program in your mail path is
2824 inserting the blank line and replace that. If you can't do either
2825 of these things, pick a different MDA (such as maildrop) and
2826 declare it with the '<code>mda</code>' option.</p>
2828 <h2><a id="X2" name="X2">X2. My mail client can't see a Subject
2831 <p>First, see <a href="#X1">X1</a>. This is quite probably the same
2832 problem (X-POP3-Rcpt header or something similar being inserted by
2833 the server and choked on by an old version of
2834 <em>deliver</em>).</p>
2836 <p>The O'Reilly sendmail book does warn that IDA sendmail doesn't
2837 process X- headers correctly. If this is your problem, all I can
2838 suggest is replacing IDA sendmail, because it's broken and not
2839 RFC822 conformant.</p>
2841 <h2><a id="X3" name="X3">X3. Messages containing "From" at the start of
2842 line are being split.</a></h2>
2844 <p>If you know the messages aren't split in your server mailbox,
2845 then this is a problem with your POP/IMAP server, your client-side
2846 SMTP listener or your local delivery agent. Fetchmail cannot split
2849 <p>Some POP server daemons ignore Content-Length headers and split
2850 messages on From lines. We have one report that the 2.1 version of
2851 the BSD popper program (as distributed on Solaris 2.5 and
2852 elsewhere) is broken this way.</p>
2854 <p>You can test this. Declare an mda of 'cat' and send yourself one
2855 piece of mail containing "From" at start of a line. If you see a
2856 split message, your POP/IMAP server is at fault. Upgrade to a more
2859 <p>Sendmail and other SMTP listeners don't split RFC822 messages
2860 either. What's probably happening is either sendmail's local
2861 delivery agent or your mail reader are not quite RFC822-conformant
2862 and are breaking messages on what it thinks are Unix-style From
2863 headers. You can figure out which by looking at your client-side
2864 mailbox with vi or more. If the message is already split in your
2865 mailbox, your local delivery agent is the problem. If it's not,
2866 your mailreader is the problem.</p>
2868 <p>If you can't replace the offending program, take a look at your
2869 sendmail.cf file. There will likely be a line something like</p>
2872 Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
2875 <p>describing your local delivery agent. Try inserting the 'E'
2876 option in the flags part (the F= string). This will make sendmail
2877 turn each dangerous start-of-line From into a >From, preventing
2878 programs further downstream from acting up.</p>
2880 <h2><a id="X4" name="X4">X4.</a> <a id="generic_mangling"
2881 name="generic_mangling">My mail is being mangled in a new and
2882 different way</a></h2>
2884 <p>The first thing you need to do is pin down what program is doing
2885 the mangling. We don't like getting bug reports about fetchmail
2886 that are actually due to some other program's malfeasance, so
2887 please go through this diagnostic sequence before sending us a
2890 <p>There are five possible culprits to consider, listed here in the
2891 order they pass your mail:</p>
2894 <li>Programs upstream of your server mailbox.</li>
2896 <li>The POP or IMAP server on your mailserver host.</li>
2898 <li>The fetchmail program itself.</li>
2900 <li>Your local sendmail.</li>
2902 <li>Your LDA (local delivery agent), as called by sendmail or
2903 specified by <code>mda</code>.</li>
2906 <p>Often it happens that fetchmail itself is OK, but using it
2907 exposes pre-existing bugs in your downstream software, or your
2908 downstream software has a bad interaction with POP/IMAP. You need
2909 to pin down exactly where the message is being garbled in order to
2910 deduce what is actually going on.</p>
2912 <p>The first thing to do is send yourself a test message, and
2913 retrieve it with a .fetchmailrc entry containing the following (or
2914 by running with the equivalent command-line options):</p>
2917 mda "cat >MBOX" keep fetchall
2920 <p>This will capture what fetchmail gets from the server, except
2921 for (a) the extra Received header line fetchmail prepends, (b)
2922 header address changes due to <code>rewrite</code>, and (c) any
2923 end-of-line changes due to the <code>forcecr</code> and
2924 <code>stripcr</code> options. MBOX will in fact contain what
2925 programs downstream of fetchmail see.</p>
2927 <p>The most common causes of mangling are bugs and
2928 misconfigurations in those downstream programs. If MBOX looks
2929 unmangled, you will know that is what is going on and that it is
2930 not fetchmail's problem. Take a look at the other FAQ items in this
2931 section for possible clues about how to fix your problem.</p>
2933 <p>If MBOX looks mangled, the next thing to do is compare it with
2934 your actual server mailbox (if possible). That's why you specified
2935 <code>keep</code>, so the server copy would not be deleted. If your
2936 server mailbox looks mangled, programs upstream of your server
2937 mailbox are at fault. Unfortunately there is probably little you
2938 can do about this aside from complaining to your site postmaster,
2939 and nothing at all fetchmail can do about it!</p>
2941 <p>More likely you'll find that the server copy looks OK. In that
2942 case either the POP/IMAP server or fetchmail is doing the mangling.
2943 To determine which, you'll need to telnet to the server port and
2944 simulate a fetchmail session yourself. This is not actually hard
2945 (both POP3 and IMAP are simple, text-only, line-oriented protocols)
2946 but requires some attention to detail. You should be able to use a
2947 fetchmail -v log as a model for a session, but remember that the
2948 "*" in your LOGIN or PASS command dump has to be replaced with your
2949 actual password.</p>
2951 <p>The objective of manually simulating fetchmail is so you can see
2952 exactly what fetchmail sees. If you see a mangled message, then
2953 your server is at fault, and you probably need to complain to your
2954 mailserver administrators. However, we like to know what the broken
2955 servers are so we can warn people away from them. So please send us
2956 a transcript of the session including the mangling <em>and the
2957 server's initial greeting line</em>. Please tell us anything else
2958 you think might be useful about the server, like the server host's
2959 operating system.</p>
2961 <p>If your manual fetchmail simulation shows an unmangled message,
2962 congratulations. You've found an actual fetchmail bug, which is a
2963 pretty rare thing these days. Complain to us and we'll fix it.
2964 Please include the session transcript of your manual fetchmail
2965 simulation along with the other things described in the FAQ entry
2966 on <a href="#G3">reporting bugs</a>.</p>
2968 <h2><a id="X5" name="X5"><strike>X5. Using POP3, retrievals seems to be
2969 fetching too much!</strike></a></h2>
2971 <p>The information that used to be here pertained to fetchmail 4.4.7 or
2972 older, which should not be used. Use a recent fetchmail version.</p>
2974 <p>Workaround: set the <code>fetchall</code> option. Under POP3
2975 this has the side effect of forcing RETR use.</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?i</strike></a></h2>
3366 <p>The answer that used to be here made no sense.</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>