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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 You can register a secret on the host (using
631 <code>popauth(8)</code> or some program like it). 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.</p>
636 <p>Alternatively, you may have Kerberos available. This may require
637 you to set up some magic files in your home directory on your
638 client machine, but means you can omit specifying any password at
641 <p>Fetchmail supports two different Kerberos schemes. One is a POP3
642 variant called KPOP; consult the documentation of your mail server
643 to see if you have it (one clue is the string "krb-IV" in the
644 greeting line on port 110). The other is an IMAP and POP3 facility
645 described by RFC1731 and RFC1734. You can tell if this one is
646 present by looking for AUTH=KERBEROS_V4 in the CAPABILITY
649 <p>If you are fetching mail from a CompuServe POP3 account, you can
650 use their RPA authentication (which works much like APOP). See <a
651 href="#I1">I1</a> for details. If you are fetching mail from
652 Microsoft Exchange using IMAP, you will be able to use NTLM.</p>
654 <p>Your POP3 server may have the RFC1938 OTP capability to use
655 one-time passwords (if it doesn't, you can get OTP patches for the
656 2.2 version of the Qualcomm popper from <a href="#cmetz">Craig
657 Metz</a>). To check this, look for the string "otp-" in the
658 greeting line. If you see it, and your fetchmail was built with
659 OPIE support compiled in (see the distribution INSTALL file),
660 fetchmail will detect it also. When using OTP, you will specify a
661 password but it will not be sent en clair.</p>
663 <p>You can get both POP3 and IMAP OTP patches from <a id="cmetz"
664 name="cmetz">Craig Metz</a> at <a
665 href="http://www.inner.net/opie">http://www.inner.net/opie</a>.</p>
667 <p>These patches use a SASL authentication method named "X-OTP"
668 because there is not currently a standard way to do this; fetchmail
669 also uses this method, so the two will interoperate happily. They
670 better, because this is how Craig gets his mail ;-)</p>
672 <p>Finally, you can use <a href="#K5">SSL</a> for complete
673 end-to-end encryption if you have an SSL-enabled mailserver.</p>
675 <h2><a id="G11" name="G11">G11. Is any special configuration needed
676 to use a dynamic IP address?</a></h2>
678 <p>Yes. In order to avoid giving indigestion to certain picky MTAs
679 (notably <a href="#T3">exim</a>), fetchmail always makes the RCPT TO
680 address it feeds the MTA a fully qualified one with a hostname
681 part. Normally it does this by appending @ and "localhost", but
682 when you are using Kerberos or ETRN mode it will append @ and your
683 machine's fully-qualified domain name (FQDN).</p>
685 <p>Appending the FQDN can create problems when fetchmail is running
686 in daemon mode and outlasts the dynamic IP address assignment your
687 client machine had when it started up.</p>
689 <p>Since the new IP address (looked up at RCPT TO interpretation
690 time) doesn't match the original, the most benign possible result
691 is that your MTA thinks it's seeing a relaying attempt and refuses.
692 More frequently, fetchmail will try to connect to a nonexistent
693 host address and time out. Worst case, you could up forwarding your
694 mail to the wrong machine!</p>
696 <p>Use the <code>smtpaddress</code> option to force the appended
697 hostname to one with a (fixed) IP address of 127.0.0.1 in your
698 <code>/etc/hosts</code>. (The name 'localhost' will usually work;
699 or you can use the IP address itself.)</p>
701 <p>Only one fetchmail option interacts directly with your IP
702 address, '<code>interface</code>'. This option can be used to set
703 the gateway device and restrict the IP address range fetchmail will
704 use. Such a restriction is sometimes useful for security reasons,
705 especially on multihomed sites. See <a href="#C3">C3</a>.</p>
707 <p>I recommend against trying to set up the <code>interface</code>
708 option when initially developing your poll configuration – it's
709 never necessary to do this just to get a link working. Get the link
710 working first, observe the actual address range you see on
711 connections, and add an <code>interface</code> option (if you need
714 <p>You can't use ETRN if you have a dynamic IP address (your ISP
715 changes your IP address occasionally, possibly with every connect).
716 You need to have your own registered domain and a definite IP
717 address registered for that domain. The server needs to be
718 configured to accept mail for your domain but then queue it to
719 forward to your machine. ETRN just tells to server to flush its
720 queue for your domain. Fetchmail doesn't actually get the mail in
723 <p>You can use On-Demand Mail Relay (ODMR) with a dynamic IP
724 address; that's what it was designed for, and it provides
725 capabilities very similar to ETRN. Unfortunately ODMR servers are
726 still not yet widely deployed, as of 2006.</p>
728 <p>If you're using a dynamic-IP configuration, one other
729 (non-fetchmail) problem you may run into with outgoing mail is that
730 some sites will bounce your email because the hostname you're giving
731 them isn't real (and doesn't match what they get doing a reverse
732 DNS on your dynamically-assigned IP address). If this happens, you
733 need to hack your sendmail so it masquerades as your host.
740 <p>in your <code>sendmail.cf</code> will work, or you can set</p>
743 MASQUERADE_AS(smarthost.here)
746 <p>in the m4 configuration and do a reconfigure. (In both cases,
747 replace <code>smarthost.here</code> with the actual name of your
748 mailhost.) See the <a
749 href="http://www.lege.com/sendmail-FAQ.txt">sendmail FAQ</a> for
752 <h2><a id="G12" name="G12">G12. Is any special configuration needed
753 to use firewalls?</a></h2>
755 <p>No. You can use fetchmail with SOCKS, the standard tool for
756 indirecting TCP/IP through a firewall. You can find out about
757 SOCKS, and download the SOCKS software including server and client
758 code, at the <a href="http://www.socks.nec.com/">SOCKS distribution
761 <p>The specific recipe for using fetchmail with a firewall is at <a
762 href="#K1">K1</a></p>
764 <h2><a id="G13" name="G13">G13. Is any special configuration needed
765 to <em>send</em> mail?</a></h2>
767 <p>A user asks: but how do we send mail out to the POP3 server? Do
768 I need to implement another tool or will fetchmail do this too?</p>
770 <p>Fetchmail only handles the receiving side. The sendmail or other
771 preinstalled MTA on your client machine will handle sending mail
772 automatically; it will ship mail that is submitted while the
773 connection is active, and put mail that is submitted while the
774 connection is inactive into the outgoing queue.</p>
776 <p>Normally, sendmail is also run periodically (every 15 minutes on
777 most Linux systems) in a mode that tries to ship all the mail in
778 the outgoing queue. If you have set up something like pppd to
779 automatically dial out when your kernel is called to open a TCP/IP
780 connection, this will ensure that the mail gets out.</p>
782 <h2><a id="G14" name="G14">G14. Is fetchmail
783 Y2K-compliant?</a></h2>
785 <p>Fetchmail is fully Y2K-compliant.</p>
787 <p>Fetchmail could theoretically have problems when the 32-bit
788 time_t counters roll over in 2038, but I doubt it. Timestamps
789 aren't used for anything but log entry generation. Anyway, if you
790 aren't running on a 64-bit machine by then, you'll deserve to
793 <h2><a id="G15" name="G15">G15. Is there a way in fetchmail to
794 support disconnected IMAP mode?</a></h2>
796 <p>No. Fetchmail is a mail transport agent, best understood as a
797 protocol gateway between POP3/IMAP servers and SMTP. Disconnected
798 operation requires an elaborate interactive client. It's a very
799 different problem.</p>
801 <h2><a id="G16" name="G16">G16. How will fetchmail perform under
802 heavy loads?</a></h2>
804 <p>Fetchmail streams message bodies line-by-line; the most core it
805 ever requires per message is enough memory to hold the RFC822
806 header, and that storage is freed when body processing begins. It
807 is, accordingly, quite economical in its use of memory. It will store
808 the UID or UIDL data in core however, which can become considerable if
809 you are keeping lots of messages on the server.</p>
811 <p>After startup time, a fetchmail running in daemon mode stats its
812 configuration file once per poll cycle to see whether it has
813 changed and should be rescanned. Other than that, a fetchmail in
814 normal operation doesn't touch the disk at all; that job is left up
815 to the MTA or MDA the fetchmail talks to.</p>
817 <p>Fetchmail's performance is usually bottlenecked by latency on
818 the POP server or (less often) on the TCP/IP link to the server.
819 This is not a problem readily solved by tuning fetchmail, or even
820 by buying more TCP/IP capacity (which tends to improve bandwidth
821 but not necessarily latency).</p>
824 <h1>Build-time problems</h1>
825 <h2><a id="B1" name="B1"><strike>B1. Make coughs and dies when building on
826 FreeBSD.</strike></a></h2>
828 <p style="font-style:italic;">As of release 6.3.0, fetchmail's
829 Makefile[.in] should work flawlessly with BSD's portable make used on
830 FreeBSD. With older releases, use GNU make (usually installed as
831 <code>gmake</code>; otherwise try <kbd>pkg_add -r gmake</kbd>).</p>
833 <h2><a id="B2" name="B2">B2. Lex bombs out while building the
834 fetchmail lexer.</a></h2>
836 <p>fetchmail 6.3.0 and newer ship with the lexer and parser in .c
837 formats, so you do not need to use lex unless you hacked the .l or .y
840 <p>fetchmail's lexer has been developed with GNU flex and uses some of
841 its specialties, so the lexer cannot be compiled with the lex tools
842 shipped by some UNIX vendors (HP, SGI, Sun).</p>
844 <h2><a id="B3" name="B3">B3. I get link failures when I try to
845 build fetchmail.</a></h2>
847 <p>If you get errors resembling these:</p>
850 mxget.o(.text+0x35): undefined referenceto '__res_search'
851 mxget.o(.text+0x99): undefined reference to '__dn_skipname'
852 mxget.o(.text+0x11c): undefined reference to '__dn_expand'
853 mxget.o(.text+0x187): undefined reference to '__dn_expand'
854 make: *** [fetchmail] Error 1
857 <p>then you must add "-lresolv" to the LOADLIBS line in your
858 Makefile once you have installed the 'bind' package.</p>
860 <p>If you get link errors involving <tt>dcgettext</tt>, like
864 rcfile_y.o: In function 'yyparse':
865 rcfile_y.o(.text+0x3aa): undefined reference to 'dcgettext__'
866 rcfile_y.o(.text+0x4f2): undefined reference to 'dcgettext__'
867 rcfile_y.o(.text+0x5ee): undefined reference to 'dcgettext__'
868 rcfile_y.o: In function 'yyerror':
869 rcfile_y.o(.text+0xc7c): undefined reference to 'dcgettext__'
870 rcfile_y.o(.text+0xcc8): undefined reference to 'dcgettext__'
871 rcfile_y.o(.text+0xdf9): more undefined references to 'dcgettext__' follow
874 <p>install an up to date version of GNU gettext, reconfigure and rebuild
875 fetchmail. If that does not help, reconfigure with '--disable-nls' added
876 to the "./configure" command and rebuild.</p>
878 <h2><a id="B4" name="B4">B4. I get build failures in the intl
881 <p>Reconfigure with <tt>--disable-nls</tt> and recompile.</p>
884 <h1>Fetchmail configuration file grammar questions</h1>
885 <h2><a id="F1" name="F1">F1. Why does my old .fetchmailrc file no
886 longer work?</a></h2>
888 <h3>If your file predates 6.3.0</h3>
890 <p>The <tt>netsec</tt> option was discontinued and needs to be
893 <h3>If your file predates 5.8.9</h3>
895 <p>If you were using ETRN mode, change your <tt>smtphost</tt>
896 option to a <tt>fetchdomains</tt> option.</p>
898 <h3>If your file predates 5.8.3</h3>
900 <p>The <tt>'via localhost'</tt> special case for use with ssh tunnelling is
901 gone. Use the <tt>%h</tt> feature of <tt>plugin</tt> instead.</p>
903 <h3>If your file predates 5.6.8</h3>
905 <p>In 5.6.8, the <tt>preauth</tt> keyword and option were changed
906 back to <tt>auth</tt>. The <tt>preauth</tt> synonym will still be
907 supported through a few more point releases.</p>
909 <h3>If your file predates 5.6.5</h3>
911 <p>The <tt>imap-gss</tt>, <tt>imap-k4</tt>, and <tt>imap-login</tt>
912 protocol types are gone. This is a result of a major re-factoring
913 of the authentication machinery; fetchmail can now use Kerberos V4
914 and GSSAPI not just with IMAP but with POP3 servers that have
915 RFC1734 support for the AUTH command.</p>
917 <p>When trying to identify you to an IMAP or POP mailserver,
918 fetchmail now first tries methods that don't require a password
919 (GSSAPI, KERBEROS_IV); then it looks for methods that mask your
920 password (CRAM-MD5, X-OTP); and only if it the server doesn't
921 support any of those will it ship your password en clair.</p>
923 <p>Setting the <tt>preauth</tt> option to any value other than
924 'password' will prevent from looking for a password in your
925 <tt>.netrc</tt> file or querying for it at startup time.</p>
927 <h3>If your file predates 5.1.0</h3>
929 <p>In 5.1.0, the <tt>auth</tt> keyword and option were changed to
930 <tt>preauth</tt>.</p>
932 <h3>If your file predates 4.5.5</h3>
934 <p>If the <code>dns</code> option is on (the default), you may need
935 to make sure that any hostname you specify (for mail hosts or for
936 an SMTP target) is a canonical fully-qualified hostname). In order
937 to avoid DNS overhead and complications, fetchmail no longer tries
938 to derive the fetchmail client machine's canonical DNS name at
941 <h3>If your file predates 4.0.6:</h3>
943 <p>Just after the '<code>via</code>' option was introduced, I
944 realized that the interactions between the '<code>via</code>',
945 '<code>aka</code>', and '<code>localdomains</code>' options were
946 out of control. Their behavior had become complex and confusing, so
947 much so that I was no longer sure I understood it myself. Users
948 were being unpleasantly surprised.</p>
950 <p>Rather than add more options or crock the code, I re-thought it.
951 The redesign simplified the code and made the options more
952 orthogonal, but may have broken some complex multidrop
955 <p>Any multidrop configurations that depended on the name just
956 after the '<code>poll</code>' or '<code>skip</code>' keyword being
957 still interpreted as a DNS name for address-matching purposes, even
958 in the presence of a '<code>via</code>' option, will break.</p>
960 <p>It is theoretically possible that other unusual configurations
961 (such as those using a non-FQDN poll name to generate Kerberos IV
962 tickets) might also break; the old behavior was sufficiently murky
963 that we can't be sure. If you think this has happened to you,
964 contact the maintainer.</p>
966 <h3>If your file predates 3.9.5:</h3>
968 <p>The '<code>remote</code>' keyword has been changed to
969 '<code>folder</code>'. If you try to use the old keyword, the
970 parser will utter a warning.</p>
972 <h3>If your file predates 3.9:</h3>
974 <p>It could be because you're using a .fetchmailrc that's written
975 in the old popclient syntax without an explicit
976 '<code>username</code>' keyword leading the first user entry
977 attached to a server entry.</p>
979 <p>This error can be triggered by having a user option such as
980 '<code>keep</code>' or '<code>fetchall</code>' before the first
981 explicit username. For example, if you write</p>
984 poll openmail protocol pop3
985 keep user "Hal DeVore" there is hdevore here
988 <p>the '<code>keep</code>' option will generate an entire user
989 entry with the default username (the name of fetchmail's invoking
992 <p>The popclient compatibility syntax was removed in 4.0. It
993 complicated the configuration file grammar and confused users.</p>
995 <h3>If your file predates 2.8:</h3>
997 <p>The '<code>interface</code>', '<code>monitor</code>' and
998 '<code>batchlimit</code>' options changed after 2.8.</p>
1000 <p>They used to be global options with '<code>set</code>' syntax
1001 like the batchlimit and logfile options. Now they're per-server
1002 options, like '<code>protocol</code>'.</p>
1004 <p>If you had something like</p>
1007 set interface = "sl0/10.0.2.15"
1010 <p>in your .fetchmailrc file, simply delete that line and insert
1011 'interface sl0/10.0.2.15' in the server options part of your
1012 'defaults' declaration.</p>
1014 <p>Do similarly for any '<code>monitor</code>' or
1015 '<code>batchlimit</code>' options.</p>
1017 <h2><a id="F2" name="F2">F2. The .fetchmailrc parser won't accept
1018 my all-numeric user name.</a></h2>
1020 <p>Either upgrade to a post-5.0.5 fetchmail or put string quotes
1023 <p>The configuration file parser in older fetchmail versions
1024 treated any all-numeric token as a number, which confused it when
1025 it was expecting a name. String quoting forces the token's
1028 <p>The lexical analyzer in 5.0.6 and beyond is smarter and assumes
1029 any token following "username" or "password" is a string.</p>
1031 <h2><a id="F3" name="F3">F3. The .fetchmailrc parser won't accept
1032 my host or username beginning with 'no'.</a></h2>
1034 <p>See <a href="#F2">F2</a>. You're caught in an unfortunate crack
1035 between the newer-style syntax for negated options ('no keep', 'no
1036 rewrite' etc.) and the older style run-on syntax ('nokeep',
1037 'norewrite' etc.).</p>
1039 <p>Upgrade to a 5.0.6 or later fetchmail, or put string quotes
1040 around your token.</p>
1042 <h2><a id="F4" name="F4">F4. I'm getting a 'parse error' message I
1043 don't understand.</a></h2>
1045 <p>The most common cause of mysterious parse errors is putting a
1046 server option after a user option. Check the manual page; you'll
1047 probably find that by moving one or more options closer to the
1048 'poll' keyword you can eliminate the problem.</p>
1050 <p>Yes, I know these ordering restrictions are hard to understand.
1051 Unfortunately, they're necessary in order to allow the 'defaults'
1052 feature to work.</p>
1055 <h1>Configuration questions</h1>
1056 <h2><a id="C1" name="C1">C1. Why do I need a .fetchmailrc when
1057 running as root on my own machine?</a></h2>
1059 <p>Ian T. Zimmerman <itz@rahul.net> asked:</p>
1061 <p>On the machine where I'm the only real user, I run fetchmail as
1062 root from a cron job, like this:</p>
1065 fetchmail -u "itz" -p POP3 -s bolero.rahul.net
1068 <p>This used to work as is (with no .fetchmailrc file in root's
1069 home directory) with the last version I had (1.7 or 1.8, I don't
1070 remember). But with 2.0, it RECPs all mail to the local root user,
1071 unless I create a .fetchmailrc in root's home directory
1075 skip bolero.rahul.net proto POP3
1079 <p>It won't work if the second line is just "<code>user
1080 itz</code>". This is silly.</p>
1082 <p>It seems fetchmail decides to RECP the 'default local user'
1083 (i.e. the uid running fetchmail) unless there are local aliases,
1084 and the 'default' aliases (itz->itz) don't count. They
1089 <p>No they shouldn't. I thought about this for a while, and I don't
1090 much like the conclusion I reached, but it's unavoidable. The
1091 problem is that fetchmail has no way to know, in general, that a
1092 local user 'itz' actually exists.</p>
1094 <p>"Ah!" you say, "Why doesn't it check the password file to see if
1095 the remote name matches a local one?" Well, there are two
1098 <p>One: it's not always possible. Suppose you have an SMTP host
1099 declared that's not the machine fetchmail is running on? You
1102 <p>Two: How do you know server itz and SMTP-host itz are the same
1103 person? They might not be, and fetchmail shouldn't assume they are
1104 unless local-itz can explicitly produce credentials to prove it
1105 (that is, the server-itz password in local-itz's .fetchmailrc
1108 <p>Once you start running down possible failure modes and thinking
1109 about ways to tinker with the mapping rules, you'll quickly find
1110 that all the alternatives to the present default are worse or
1111 unacceptably more complicated or both.</p>
1113 <h2><a id="C2" name="C2">C2. How can I arrange for a fetchmail
1114 daemon to get killed when I log out?</a></h2>
1116 <p>The easiest way to dispatch fetchmail on logout (which will work
1117 reliably only if you have just one login going at any time) is to
1118 arrange for the command 'fetchmail -q' to be called on logout.
1119 Under bash, you can arrange this by putting 'fetchmail -q' in the
1120 file '~/.bash_logout'. Most csh variants execute '~/.logout' on
1121 logout. For other shells, consult your shell manual page.</p>
1123 <p>Automatic startup/shutdown of fetchmail is a little harder to
1124 arrange if you may have multiple login sessions going. In the
1125 contrib subdirectory of the fetchmail distribution there is some
1126 shell code you can add to your .bash_login and .bash_logout
1127 profiles that will accomplish this. Thank James Laferriere
1128 <babydr@nwrain.net> for it.</p>
1130 <p>Some people start up and shut down fetchmail using the ppp-up
1131 and ppp-down scripts of pppd.</p>
1133 <h2><a id="C3" name="C3">C3. How do I know what interface and
1134 address to use with --interface?</a></h2>
1136 <p>This depends a lot on your local networking configuration (and
1137 right now you can't use it at all except under Linux and the newer
1138 BSDs). However, here are some important rules of thumb that can
1139 help. If they don't work, ask your local sysop or your Internet
1142 <p>First, you may not need to use --interface at all. If your
1143 machine only ever does SLIP or PPP to one provider, it's almost
1144 certainly by a point to point modem connection to your provider's
1145 local subnet that's pretty secure against snooping (unless someone
1146 can tap your phone or the provider's local subnet!). Under these
1147 circumstances, specifying an interface address is fairly
1150 <p>What the option is really for is sites that use more than one
1151 provider. Under these circumstances, typically one of your provider
1152 IP addresses is your mailserver (reachable fairly securely via the
1153 modem and provider's subnet) but the others might ship your packets
1154 (including your password) over unknown portions of the general
1155 Internet that could be vulnerable to snooping. What you'll use
1156 --interface for is to make sure your password only goes over the
1157 one secure link.</p>
1159 <p>To determine the device:</p>
1162 <li>If you're using a SLIP link, the correct device is probably
1165 <li>If you're using a PPP link, the correct device is probably
1168 <li>If you're using a direct connection over a local network such
1169 as an ethernet, use the command 'netstat -r' to look at your
1170 routing table. Try to match your mailserver name to a destination
1171 entry; if you don't see it in the first column, use the 'default'
1172 entry. The device name will be in the rightmost column.</li>
1175 <p>To determine the address and netmask:</p>
1178 <li>If you're talking to slirp, the correct address is probably
1179 10.0.2.15, with no netmask specified. (It's possible to configure
1180 slirp to present other addresses, but that's the default.)</li>
1182 <li>If you have a static IP address, run 'ifconfig <device>',
1183 where <device> is whichever one you've determined. Use the IP
1184 address given after "inet addr:". That is the IP address for your
1185 end of the link, and is what you need. You won't need to specify a
1188 <li>If you have a dynamic IP address, your connection IP will vary
1189 randomly over some given range (that is, some number of the least
1190 significant bits change from connection to connection). You need to
1191 declare an address with the variable bits zero and a complementary
1192 netmask that sets the range.</li>
1195 <p>To illustrate the rule for dynamic IP addresses, let's suppose
1196 you're hooked up via SLIP and your IP provider tells you that the
1197 dynamic address pool is 255 addresses ranging from 205.164.136.1 to
1198 205.164.136.255. Then</p>
1201 interface "sl0/205.164.136.0/255.255.255.0"
1204 <p>would work. To range over any value of the last two octets
1205 (65536 addresses) you would use</p>
1208 interface "sl0/205.164.0.0/255.255.0.0"
1211 <h2><a id="C4" name="C4">C4. How can I set up support for
1212 sendmail's anti-spam features?</a></h2>
1214 <p>This answer covers versions of sendmail from 8.9.3-20 (the
1215 version installed in Red Hat 6.2) upwards. If you have an older
1216 version, upgrade to sendmail 8.9.</p>
1218 <p>Stock sendmails can now do anti-spam exclusions based on a
1219 database of filter rules. The human-readable form of the database
1220 is at <tt>/etc/mail/access</tt>. The database itself is at
1221 <tt>/etc/mail/access.db</tt>.</p>
1223 <p>The table itself uses email addresses, domain names, and network
1224 numbers as keys. For example,</p>
1227 spammer@aol.com REJECT
1228 cyberspammer.com REJECT
1232 <p>would refuse mail from spammer@aol.com, any user from
1233 cyberspammer.com (or any host within the cyberspammer.com domain),
1234 and any host on the 192.168.212.* network. (This feature can be
1235 used to do other things as well; see the <a
1236 href="http://www.sendmail.org/m4/anti_spam.html">sendmail
1237 documentation</a> for details)</p>
1239 <p>To actually set up the database, run</p>
1242 makemap hash deny <deny
1245 <p>in /etc/mail.</p>
1247 <p>To test, send a message to your mailing address from that host
1248 and then pop off the message with fetchmail, using the -v argument.
1249 You can monitor the SMTP transaction, and when the FROM address is
1250 parsed, if sendmail sees that it is an address in spamlist,
1251 fetchmail will flush and delete it.</p>
1253 <p>Under no circumstances put your <strong>mailhost</strong> or
1254 <strong>any host you accept mail from</strong> using fetchmail into
1255 your reject file. You <strong>will</strong> lose mail if you do
1258 <h2><a id="C5" name="C5">C5. How can I poll some of my mailboxes
1259 more/less often than others?</a></h2>
1261 <p>Use the <cite>interval</cite> keyword on the ones that should be
1262 checked less often. For example, if you do a poll every 5 minutes,
1263 and want to poll some mailboxes every 5 minutes and some every 30
1264 minutes, use something like this:</p>
1267 poll mainsite.example.com proto pop3 user ....
1268 poll secondary.example.com proto pop3 interval 6 user ...
1271 <p>Then secondary.example.com will be polled every 6th time that
1272 mainsite.example.com is polled, which with a polling interval of
1273 every 5 minutes means that secondary.example.com will be polled
1274 every 30 minutes.</p>
1276 <h2><a id="C6" name="C6">Fetchmail works OK started up manually,
1277 but not from an init script.</a></h2>
1279 <p>Often, startup scripts have a different environment than an
1280 interactive login shell. For instance, $HOME might point to "/root"
1281 when you are logged in as root, but it might be either unset, or
1282 set to "/" when the startup scripts are running. That means
1283 fetchmail at startup can't find the .fetchmailrc.</p>
1285 <p>Pick a location (such as /etc/fetchmailrc) and use fetchmail's
1286 -f option to point fetchmail at it. That should solve the
1289 <h2><a id="C7" name="C7">C7. How can I forward mail to another
1292 <p>To forward mail to a host other than the one you are running
1293 fetchmail on, use the <code>smtphost</code> or
1294 <code>smtpname</code> option. See the manual page for details.</p>
1297 <h1>How to make fetchmail play nice with various MTAs</h1>
1298 <h2><a id="T1" name="T1">T1. How can I use fetchmail with
1301 <p>For most sendmails, no special configuration is required. Eric
1302 Allman tells me that if <code>FEATURE(always_add_domain)</code> is
1303 included in sendmail's configuration, you can leave the
1304 <code>rewrite</code> option off.</p>
1306 <p>If your sendmail complains "sendmail does not relay", make
1307 sure your sendmail.cf file says <code>Cwlocalhost</code> so that
1308 sendmail recognizes 'localhost' as a name of its host.</p>
1310 <p>If you're mailing from another machine on your local network,
1311 also ensure that its IP address is listed in ip_allow or name in
1312 name_allow (usually in /etc/mail/)</p>
1314 <p>If you find that your sendmail doesn't like the address
1315 'FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail that
1316 fetchmail generates), you may have to set
1317 <code>FEATURE(accept_unqualified_senders)</code>.</p>
1319 <p>Günther Leber reports that Digital Unix sendmails won't
1320 work with fetchmail. The symptom is an error message "<code>553
1321 Local configuration error, hostname not recognized as
1322 local</code>". The problem is that fetchmail normally feeds
1323 sendmail with the client machine's host address in the MAIL FROM
1324 line. These sendmails think this means they're seeing the result of
1325 a mail loop and suppress the mail. You may be able to work around
1326 this by running in <code>--invisible</code> mode.</p>
1328 <p>If you want to support multidrop mode, and you can get access to
1329 your mailserver's sendmail.cf file, it's a good idea to add this
1333 H?l?Delivered-To: $h
1336 <p>This will cause the mailserver's sendmail to reliably write the
1337 appropriate envelope address into each message before fetchmail
1338 sees it, and tell fetchmail which header it is.  With this
1339 change, multidrop mode should work reliably even when the Received
1340 header omits the envelope address (which will typically be the case
1341 when the message has multiple recipients).  However it will
1342 still not distinguish the recipients, your only advantage is that
1343 no bounce will be sent if a message is BCC addressed to multiple
1344 users at your site.  To fix even that problem, you might want
1345 to try the following hack, which is however untested and quite
1349 H?J?Delivered-To: $u
1351 Mmdrop, P=/usr/bin/procmail, F=lsDFMqSPfhnu9J,
1352 S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP/HdrToSMTP,
1353 T=DNS/RFC822/X-Unix,
1354 A=procmail -Y -a $u -d $h
1357 <p>For both hacks, you have to declare '<code>envelope
1358 "Delivered-To:"</code>' on the fetchmail side, to put the virtual
1359 domain (e.g. 'domain.com') with RELAY permission into your access
1360 file and to add a line reading '<code>domain.com
1361 local:local-pop-user</code>' for the first and '<code>domain.com
1362 mdrop:local-pop-user</code>' for the second hack to your
1365 <p>You will notice that if the mail already has a Delivered-To
1366 header, sendmail will not add another.  Further, editing
1367 sendmail.cf directly is not very comfortable.  Solutions for
1368 both problems can be found in Peter 'Rattacresh' Backes' 'hybrid'
1369 patch against sendmail.  Have a look at it, you can find it in
1370 the contrib subdirectory.</p>
1372 <p>Feel free to try Martijn Lievaart's detailed recipe in the
1373 contrib subdirectory of the fetchmail source distribution, it
1374 attempts to realize multidrop mailboxes with an external
1377 <p>If for some reason you are invoking sendmail via the
1378 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
1379 don't forget to include the -i switch. Otherwise you will
1380 occasionally get mysterious delivery failures with a SIGPIPE as the
1381 sendmail instance dies. The problem is messages with a single dot
1382 at start of a text line.</p>
1384 <h2><a id="T2" name="T2">T2. How can I use fetchmail with
1387 <h3>qmail as your local SMTP server</h3>
1389 <p>Avoid <a href="http://home.pages.de/~mandree/qmail-bugs.html">qmail,
1390 it's broken and unmaintained.</a></p>
1392 <p>Turn on the <code>forcecr</code> option; qmail's listener mode
1393 doesn't like header or message lines terminated with bare
1395 (This information contributed by Robert de Bath
1396 <robert@mayday.cix.co.uk>.)</p>
1398 <h3>qmail as your ISP's POP3 server</h3>
1400 <p>Note that qmail's POP3 server, as of version 1.03 and netqmail 1.05,
1401 miscalculates the message sizes, so you may see size-related fetchmail
1404 <p>If a mailhost is using the qmail package, then it is usually possible
1405 to set up one fetchmail link to reliably collect the mail for an entire
1408 <p>One of the basic features of qmail is the 'Delivered-To:'
1409 message header. Whenever qmail delivers a message to a local
1410 mailbox it puts the username and hostname of the envelope recipient
1411 on this line. One major reason for this is to prevent mail
1412 loops, the other is to transport envelope information which is essential
1413 for multidrop (domain-in-a-mailbox) schemes.</p>
1415 <p>To set up qmail to batch mail for a disconnected site, the
1416 ISP-mailhost will have normally put that site in its 'virtualhosts'
1417 control file so it will add a prefix to all mail addresses for this
1418 site. This results in mail sent to
1419 'username@userhost.userdom.example.com' having a 'Delivered-To:' line
1423 Delivered-To: mbox-userstr-username@userhost.userdom.example.com
1426 <p>A single host maildrop will be slightly simpler:</p>
1429 Delivered-To: mbox-userstr-username@userhost.example.com
1432 <p>The ISP can make the 'mbox-userstr-' prefix anything they choose
1433 but a string matching the user host name is likely.</p>
1435 <p>To use this line you must:</p>
1438 <li>Ensure the option '<code>envelope "Delivered-To"</code>' is in the fetchmail
1441 <li>Ensure the option '<code>qvirtual "mbox-userstr-"</code>' is
1442 in the fetchmail config file, in order to remove this prefix from the
1443 username. (added by Luca Olivetti)</li>
1445 <li>Ensure you have a <code>localdomains</code> option containing
1446 '<code>userdom.example.com</code>' or '<code>userhost.userdom.example.com</code>'
1450 <h2><a id="T3" name="T3">T3. How can I use fetchmail with
1453 <p>If you have <code>rewrite</code> on:</p>
1455 <p>There is an RFC1123 requirement that MAIL FROM and RCPT TO
1456 addresses you pass to it have to be canonical (e.g. with a fully
1457 qualified hostname part). Therefore fetchmail tries to pass fully
1458 qualified RCPT TO addresses. But exim does not by default accept
1459 'localhost' as a fully qualified domain. This can be fixed.</p>
1461 <p>In exim.conf, add 'localhost' to your local_domains declaration
1462 if it's not already present. For example, the author's site at
1463 thyrsus.com would have a line reading:</p>
1466 local_domains = thyrsus.com:localhost
1469 <p>If you have <code>rewrite</code> off:</p>
1471 <p>MAIL FROM is a potential problem if the MTAs upstream from your
1472 fetchmail don't necessarily pass canonicalized From and Return-Path
1473 addresses, and fetchmail's <code>rewrite</code> option is off. The
1474 specific case where this has come up involves bounce messages
1475 generated by sendmail on your mailer host, which have the
1476 (un-canonicalized) origin address MAILER-DAEMON.</p>
1478 <p>The right way to fix this is to enable the <code>rewrite</code>
1479 option and have fetchmail canonicalize From and Return-Path
1480 addresses with the mailserver hostname before exim sees them. This
1481 option is enabled by default, so it won't be off unless you turned
1484 <p>If you must run with <code>rewrite</code> off, there is a switch
1485 in exim's configuration files that allows it to accept domainless
1486 MAIL FROM addresses; you will have to flip it by putting the
1490 sender_unqualified_hosts = localhost
1493 <p>in the main section of the exim configuration file. Note that
1494 this will result in such messages having an incorrect domain name
1495 attached to their return address (your SMTP listener's hostname
1496 rather than that of the remote mail server).</p>
1498 <h2><a id="T4" name="T4">T4. How can I use fetchmail with
1501 <p>Smail 3.2 is very nearly plug-compatible with sendmail, and may
1502 work fine out of the box.</p>
1504 <p>We have one report that when processing multiple messages from a
1505 single fetchmail session, smail sometimes delivers them in an order
1506 other than received-date order. This can be annoying because it
1507 scrambles conversational threads. This is not fetchmail's problem,
1508 it is an smail 'feature' and has been reported to the maintainers
1511 <p>Very recent smail versions require an
1512 <code>-smtp_hello_verify</code> option in the smail config file.
1513 This overrides smail's check to see that the HELO address is
1514 actually that of the client machine, which is never going to be the
1515 case when fetchmail is in the picture. According to RFC1123 an SMTP
1516 listener <em>must</em> allow this mismatch, so smail's new behavior
1517 (introduced sometime between 3.2.0.90 and 3.2.0.95) is a bug.</p>
1519 <p>You may also need to say
1520 <code>-smtp_hello_broken_allow=127.0.0.1</code> in order for smail
1521 to accept the "localhost" that fetchmail normally appends to
1522 recipient addresses.</p>
1524 <h2><a id="T5" name="T5">T5. How can I use fetchmail with SCO's
1527 <p>MMDF itself is difficult to configure, but it turns out that
1528 connecting fetchmail to MMDF's SMTP channel isn't that hard. You
1530 href="http://aplawrence.com/Unixart/uucptofetch.html">MMDF
1531 recipe</a> that describes replacing a UUCP link with fetchmail
1534 <h2><a id="T6" name="T6">T6. How can I use fetchmail with Lotus
1537 <p>The Lotus Notes SMTP gateway tries to deduce when it should
1538 convert \n to \r\n, but its rules are not the intuitive and
1539 correct-for-RFC822 ones. Use 'forcecr'.</p>
1541 <h2><a id="T7" name="T7">T7. How can I use fetchmail with Courier
1544 <p>The courier mta doesn't like RCPT addresses that look like
1545 <code>someone@localhost</code>. Work around this with an
1546 <code>smtphost</code> or <code>smtpaddress</code>.</p>
1548 <h2><a name="T8">T8. How can I use fetchmail with vbmailshield?</a></h2>
1550 <p>vbmailshield's SMTP interpreter is broken. It doesn't understand RSET.</p>
1552 <p>As a workaround, you can set batchlimit to 1 so RSET is never used.</p>
1555 <h1>How to make fetchmail work with various servers</h1>
1556 <h2><a id="S1" name="S1"><strike>S1. How can I use fetchmail with
1557 qpopper?</strike></a></h2>
1559 <p><em>The information that used to be here was obsolete and dropped.</em></p>
1561 <h2><a id="S2" name="S2">S2. How can I use fetchmail with Microsoft
1564 <p>It's been reliably reported that Exchange 2000's POP3 support is
1565 so broken that it's unusable. One symptom is that messages without
1566 a terminating newline get the POP3 message termination dot emitted
1567 -- you guessed it -- right after the last character of the message,
1568 with no terminating newline added. This will hang fetchmail or any
1569 other RFC-compliant server. IMAP is alleged to work OK, though.</p>
1571 <p>Older versions of Exchange are semi-usable. They randomly drop
1572 attachments on the floor, though. Microsoft acknowledges this
1573 as a known bug and apparently has no plans to fix it.</p>
1575 <p>Fetchmail using IMAP supports the proprietary NTLM mode used
1576 with M$ Exchange servers. To enable this, configure fetchmail with
1577 the --enable-NTLM option and recompile it. Specify a user option
1578 value that looks like 'user@domain': the part to the left of the @
1579 will be passed as the username and the part to the right as the
1582 <p>M$ Exchange violates the POP3 and IMAP RFCs. Its LIST command
1583 does not reveal the real sizes of mail in the pop mailbox, but the
1584 sizes of the compressed versions in the exchange mail database
1585 (thanks to Arjan De Vet and Guido Van Rooij for alerting us to this
1588 <p>Fetchmail works with M$ Exchange, despite this brain damage. Two
1589 features are compromised. One is that the --limit option will not
1590 work right (it will check against compressed and not actual sizes).
1591 The other is that a too-small SIZE argument may be passed to your
1592 ESMTP listener, assuming you're using one (this should not be a
1593 problem unless the actual size of the message is above the
1594 listener's configured length limit).</p>
1596 <p>Somewhat belatedly, I've learned that there's supposed to be a
1597 registry bit that can fix this breakage:</p>
1600 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1601 System\Pop3 Compatibility
1604 <p>This is a bitmask that controls the variations from the standard
1605 protocol. The bits defined are:</p>
1608 <dt>0x00000001:</dt>
1610 <dd>Report exact message sizes for the LIST command</dd>
1612 <dt>0x00000002:</dt>
1614 <dd>Allow arbitrary linear whitespace between commands and
1617 <dt>0x00000004:</dt>
1619 <dd>Enable the LAST command</dd>
1621 <dt>0x00000008:</dt>
1623 <dd>Allow an empty PASS command (needed for users with blank
1624 passwords, but illegal in the protocol)</dd>
1626 <dt>0x00000010:</dt>
1628 <dd>Relax the length restrictions for arguments to commands
1629 (protocol requires 40, but some user names may be longer than
1632 <dt>0x00000020:</dt>
1634 <dd>Allow spaces in the argument to the USER command.</dd>
1637 <p>There's another one that may be useful to know about:</p>
1640 KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1641 System\Pop3 Performance
1645 <dt>0x00000001:</dt>
1647 <dd>Render messages to a temporary stream instead of sending
1648 directly from the database (should always be on)</dd>
1650 <dt>0x00000002: Flag unrenderable messages (instead of just failing
1651 commands) (should only be on if you are seeing the problems
1652 reported in KB Q168109)</dt>
1654 <dt>0x00000004:</dt>
1656 <dd>Return from the QUIT command before all messages have been
1660 <p>The Microsoft pod-person who revealed this information to me
1661 admitted that he couldn't find it anywhere in their public
1664 <p>Another specific problem we have seen with Exchange servers has
1665 as its symptom a response to LOGIN that says "NO Ambiguous Alias".
1666 Grant Edwards writes:</p>
1668 <p>This means that Exchange Server is too f*&#ing stupid to
1669 figure out which mailbox belongs to you. Instead of actually
1670 keeping track of which inbox belongs to which user, it uses some
1671 half-witted, guess-o-matic heuristic to try to guess your mailbox
1672 name from your username.</p>
1674 <p>In your case it doesn't work because your username maps to more
1675 than one mailbox. For some people it doesn't work because their
1676 username maps to zero mailboxes. This is yet another inept, lame,
1677 almost criminally negligent design decision from our friends in
1680 <p>You've got several options:</p>
1683 <li>Get your administrator to configure the server so that
1684 usernames and mailbox names are the same.</li>
1686 <li>Get your administrator to add an alias that maps your username
1687 explicitly to your mailbox name.</li>
1690 <p>But, the best option involves finding a server that runs better
1693 <h2><a id="S3" name="S3">S3. How can I use fetchmail with HP
1696 <p>No special configuration is required, but OpenMail versions
1697 prior to 6.0 have an annoying bug similar to the big one in <a
1698 href="#S2">Microsoft Exchange</a>. The message sizes it gives in
1699 the LIST are rounded to the nearest 1024 bytes. It also has a nasty
1700 habit of discarding headers it doesn't recognize, such as X- and
1701 Resent- headers.</p>
1703 <p>As with M$ Exchange, the only real fix for these problems is to
1704 get a POP (or preferably IMAP) server that isn't brain-dead.
1705 OpenMail's project manager claims these bugs have been fixed in
1708 <p>We've had a more recent report (December 2001) that the TOP
1709 command fails, returning only one line regardless of its argument,
1710 on something identifying itself as "OpenMail POP3 interface".</p>
1712 <h2><a id="S4" name="S4">S4. How can I use fetchmail with Novell GroupWise?</a></h2>
1714 <p>The Novell GroupWise IMAP server would be better named
1715 GroupFoolish; it is (according to the designer of IMAP) unusably
1716 broken. Among other things, it doesn't include a required content
1717 length in its BODY[TEXT] response.</p>
1719 <p>Fetchmail works around this problem, but we strongly recommend
1720 voting with your dollars for a server that isn't brain-dead.</p>
1722 <h2><a id="S5" name="S5">S5. How can I use fetchmail with
1723 InterChange?</a></h2>
1725 <p>You can't. At least not if you want to be able to see
1726 attachments. InterChange has a bug similar to the MailMax server (<a
1727 href="#S6">see below</a>):
1728 it reports the message length with attachments but doesn't download
1729 them on TOP or RETR.</p>
1731 <p>On Jan 9 2001, the people at InfiniteMail sent me mail informing
1732 me that their new 3.61.08 release of InterChange fixes this
1733 problem. I don't have any reports one way or the other yet.</p>
1735 <h2><a id="S6" name="S6">S6. How can I use fetchmail with MailMax?</a></h2>
1737 <p>You can't. At least not if you want to be able to see
1738 attachments. MailMax has a bug; it reports the message length with
1739 attachments but doesn't download them on TOP or RETR.</p>
1741 <p>Also, we're told that TOP sometimes fails to retrieve the entire
1742 message even when enough lines have been specified. The MailMax
1743 developers have acknowledged this bug as of 4 May 2000, but there
1744 is no fix yet. If you must use this server, force RETR with the
1745 <tt>fetchall</tt> option.</p>
1747 <h2><a id="S7" name="S7">S7. How can I use fetchmail with FTGate?</a></h2>
1749 <p>The FTGate V2 server (and possibly older versions as well) has a
1750 weird bug. It answers OK twice to a TOP request! Use the
1751 <code>fetchall</code> option to force use of RETR and work around
1755 <h1>How to fetchmail work with specific ISPs</h1>
1756 <h2><a id="I1" name="I1">I1. How can I use fetchmail with CompuServe RPA?</a></h2>
1758 <p>First, make sure your fetchmail has the RPA support compiled in.
1759 Stock fetchmail binaries (such as you might get from an RPM) don't.
1760 You can check this by looking at the output of <code>fetchmail
1761 -V</code>; if you see the string "+RPA" after the version ID you're
1762 good to go, otherwise you'll have to build your own from sources
1763 (see the INSTALL file in the source distribution for
1766 <p>Give your CompuServe pass-phrase in lower case as your password.
1767 Add '@compuserve.com' to your user ID so that it looks like 'user
1768 <UserID>@compuserve.com', where <UserID> can be either
1769 your numerical userID or your E-mail nickname. An RPA-enabled
1770 fetchmail will automatically check for csi.com in the POP server's
1771 greeting line. If that's found, and your user ID ends with
1772 '@compuserve.com', it will query the server to see if it is
1773 RPA-capable, and if so do an RPA transaction rather than a
1774 plain-text password handshake.</p>
1776 <p><strong>Warning:</strong> the debug (-v -v) output of fetchmail
1777 will show your pass-phrase in Unicode!</p>
1779 <p>These two .fetchmailrc entries show the difference between an
1780 RPA and non-RPA configuration:</p>
1783 # This version will use RPA
1784 poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1785 user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
1786 is LOCAL_USER here options fetchall stripcr
1788 # This version will not use RPA
1789 poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1790 user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
1791 is LOCAL_USER here options fetchall stripcr
1794 <h2><a id="I2" name="I2">I2. How can I use fetchmail with Demon
1795 Internet's SDPS?</a></h2>
1797 <h3>Single-drop mode</h3>
1799 <p>You can get fetchmail to download the email for just one user
1800 from Demon Internet's POP3 server by giving it a username
1801 consisting of your Demon user name followed by your account name,
1802 with an at-sign between them.</p>
1804 <p>For example, to download email for the user
1805 <philh@vision25.demon.co.uk>, you could use the following
1806 .fetchmailrc file:</p>
1809 set postmaster "philh"
1810 poll pop3.demon.co.uk with protocol POP3:
1811 user "philh@vision25" is philh
1814 <h3>Multi-drop mode</h3>
1816 <p>Demon Internet's SDPS service is an implementation of POP3. All
1817 messages have a Received: header added when they enter the
1818 maildrop, like this:</p>
1821 Received: from punt-1.mail.demon.net by mailstore for fred@xyz.demon.co.uk
1822 id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
1825 <p>To enable multi-drop mode you need to tell fetchmail that
1826 'mailstore' is the name of the host which accepted the mail, and
1827 let it know the hostname part(s) of your E-mail address. The
1828 following example assumes that your hostname is xyz.demon.co.uk,
1829 and that you have also bought "mail forwarding" for the domain
1830 my-company.co.uk (in which case your MTA must also be configured to
1831 accept mail sent to user@my-company.co.uk)</p>
1834 poll pop3.demon.co.uk proto pop3 aka mailstore no dns:
1835 localdomains xyz.demon.co.uk my-company.co.uk
1839 <p>Note that Demon may delete mail on the server which is more than
1840 30 days old; see their <a
1841 href="http://www.demon.net/helpdesk/producthelp/mail/sdps-tech.html/">POP3
1842 page</a> for details.</p>
1844 <h3>The SDPS extension</h3>
1846 <p>There's a different way to do multidrop. It's not necessary on
1847 Demon Internet, since fetchmail can parse Received addresses, but
1848 the person who implemented this didn't know that. It may be useful
1849 if Demon Internet ever changes mail transports.</p>
1851 <p>SDPS includes a non-standard extension for retrieving the
1852 envelope of a message (*ENV), which fetchmail optionally supports
1853 if compiled with the --enable-SDPS option. If you have it, the
1854 first line of the fetchmail -V response will include the string
1857 <p>Once you have SDPS compiled in, fetchmail in POP3 mode will
1858 automatically detect when it's talking to a Demon Internet host in
1859 multidrop mode, and use the *ENV extension to get an envelope To
1862 <p>The autodetection works by looking at the hostname in the POP3
1863 greeting line; if you're accessing Demon Internet through a proxy
1864 it may fail. To force SDPS mode, pick "sdps" as your protocol.</p>
1866 <h2><a id="I3" name="I3">I3. How can I use fetchmail with usa.net's
1869 <p>Enable '<code>fetchall</code>'. A user reports that the 2.2
1870 version of USA.NET's POP server reports that you must use the
1871 '<code>fetchall</code>' option to make sure that all of the mail is
1872 retrieved, otherwise some may be left on the server. This is almost
1873 certainly a server bug.</p>
1875 <p>The usa.net servers (at least in their 2.2 version, June 1998)
1876 don't handle the TOP command properly, either. Regardless of the
1877 argument you give it, they retrieve only about 10 lines of the
1878 message. Fetchmail normally uses TOP for message retrieval in order
1879 to avoid marking messages seen, but '<code>fetchall</code>' forces
1880 it to use RETR instead.</p>
1882 <p>Also, we're told USA.NET adds a ton of hops to your messages.
1883 You may need to raise the MaxHopCount parameter in your sendmail.cf
1884 to avoid having fetched mail rejected.</p>
1886 <h2><a id="I4" name="I4">I4. How can I use fetchmail with geocities
1887 POP3 servers?</a></h2>
1889 <p>Nathan Cutler reports that the the mail.geocities.com POP3
1890 servers fail to include the first Received line of the message in
1891 the send to fetchmail. This can solve problems if your MUA
1892 interprets Received continuations as body lines and doesn't parse
1893 any of the following headers.</p>
1895 <p>Workaround is to use "mda" keyword or "--mda" switch:</p>
1898 mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
1901 <p>Replace \t with exactly one tabulation character.</p>
1903 <p>You should also consider using "fetchall" option because
1904 Geocities' servers sometimes think that the first 45 messages have
1905 already been read.</p>
1907 <h2><a id="I5" name="I5">I5. How can I use fetchmail with Hotmail or Lycos Webmail?</a></h2>
1909 <p>You can't directly. But you can use fetchmail with hotmail or lycos
1910 webmail with the help of the <a
1911 href='http://people.freenet.de/courierdave/'>HotWayDaemon</a>
1912 daemon. You don't even need to install hotwayd as a daemon in
1913 <samp>inetd.conf</samp> but can use it as a plugin. Your
1914 configuration should look like this:</p>
1917 poll localhost protocol pop3 tracepolls
1918 plugin "/usr/local/sbin/hotwayd -l 0 -p yourproxy:yourproxyport"
1919 username "youremail@hotmail.com" password "yourpassword"
1923 <p>As a second option you may consider using <a
1924 href="http://linux.cudeso.be/linuxdoc/gotmail.php">gotmail</a>.</p>
1926 <h2><a id="I6" name="I6">I6. How can I use fetchmail with MSN?</a></h2>
1928 <p>You can't. MSN uses something that looks like POP3, except the
1929 authentication part is nonstandard. And of course they don't
1930 document it, so nobody but their Windows clients can speak it.</p>
1932 <p>This is a customer lock-in tactic; we recommend boycotting MSN
1933 as the only appropriate response.</p>
1935 <p>As of 5.0.8, we have support for the client side of NTLM
1936 authentication. It's possible this may enable fetchmail to talk to
1937 MSN; if so, somebody should report it so this FAQ can be
1940 <h2><a id="I7" name="I7">I7. How can I use fetchmail with SpryNet?</a></h2>
1942 <p>The SpryNet POP3 servers mark a message queried with TOP as
1943 seen. This means that if your connection drops in mid-message, it
1944 may end up invisibly stuck on your mail spool. Use the
1945 <code>fetchall</code> flag to ensure that it's recovered on the
1948 <h2><a id="I8" name="I8">I8. How can I use fetchmail with comcast.net or
1949 other Maillennium servers?</a></h2>
1951 <p>Stock fetchmail will work with a
1952 Maillennium POP3/PROXY server... <em>but</em> this server will
1953 truncate "TOP" responses after 64 - 82 kB (we have varying reports),
1954 in violation of Internet Standard #53 aka. RFC-1939 (POP3). Don't
1955 mistake this for a fetchmail bug. (Reported July 2003.) Comcast
1956 documented they haven't understood what this is about in <a
1957 href="http://lists.ccil.org/pipermail/fetchmail-friends/2004-April/008523.html">two
1958 messages from April 2004.</a></p>
1960 <p>Beginning with version 6.3.2, fetchmail will fall back to the RETR
1961 command if the greeting string contains "Maillennium POP3/PROXY server",
1962 and print a warning message. This means however that fetchmail has no
1963 means to prevent the "seen" flag from being set on the server (Note that
1964 officially, POP3 has no notion of seen tracking, but it works for some
1967 <p>Workaround for older versions: use the <tt>fetchall</tt> option.</p>
1970 <h1>How to set up well-known security and authentication
1972 <h2><a id="K1" name="K1">K1. How can I use fetchmail with SOCKS?</a></h2>
1974 <p>Giuseppe Guerini added a <kbd>--with-socks</kbd> compile-time option
1975 that supports linking with socks library. If you specify the value of
1976 this option as "yes", the configure script will try to find the Rconnect
1977 library and set the makefile up to link it. You can also specify a
1978 directory containing the Rconnect library.</p>
1980 <p>Alan Schmitt has added a similar <kbd>--with-socks5</kbd> option that may
1981 work better if you have a recent version of the SOCKS library.</p>
1983 <p>In either case, fetchmail has no direct configuration hooks, but you
1984 can specify which socks configuration file the library should read by
1985 means of the <tt>SOCKS_CONF</tt> environment variable. In order to
1986 bypass the SOCKS proxy altogether, you could run (adding your usual
1987 options to the end of this line):</p>
1989 <pre>env SOCKS_CONF=/dev/null fetchmail</pre>
1991 <h2><a id="K2" name="K2">K2. How can I use fetchmail with IPv6 and
1994 <p>To use fetchmail with IPv6, you need a system that supports
1995 IPv6, the "Basic Socket Interface Extensions for IPv6" (RFC 2133).
1998 <p>The NRL IPv6+IPsec software distribution can be obtained from:
2000 href="http://web.mit.edu/network/isakmp/">http://web.mit.edu/network/isakmp/</a></p>
2002 <p>More information on using IPv6 with Linux can be obtained
2007 href="http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html">
2008 http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html</a></li>
2011 <h2><a id="K3" name="K3">K3. How can I get fetchmail to work with
2014 <p>Use the <tt>plugin</tt> option. This is dead simple with
2018 plugin "ssh %h /usr/sbin/imapd"
2021 <p>You may have to use a different absolute pathname, whatever the
2022 location of imapd on your mailserver is. This option tells
2023 fetchmail that instead of opening a connection on the server's port
2024 143 and doing standard IMAP authentication, fetchmail should ssh to
2025 the server and run imapd, using the more secure ssh authentication
2026 (as well as getting ssh's end-to-end encryption). Most IMAP daemons
2027 will detect that they've been called from the command line and
2028 assume the connection is preauthenticated.</p>
2030 <p>POP3 daemons aren't quite as smart. They won't know they are
2031 preauthenticated in this mode, so you'll actually have to ship your
2032 password. It will be under ssh encryption, though, so that
2033 shouldn't be a problem.</p>
2035 <h2><a id="K4" name="K4">K4. What do I have to do to use the
2036 IMAP-GSS protocol?</a></h2>
2038 <p>Fetchmail can use RFC1731 GSSAPI authorization to safely
2039 identify you to your IMAP server, as long as you can share
2040 Kerberos V credentials with your mail host and you have a GSSAPI-capable
2041 IMAP server - those are few.</p>
2043 <p>fetchmail does not compile in support for GSS by
2044 default, since it requires libraries from the Kerberos V
2045 distribution (available via FTP at <a
2046 href="ftp://athena-dist.mit.edu/pub/ATHENA/kerberos">athena-dist.mit.edu</a>).
2047 If you have these, compiling in GSS support is simple: add a
2048 <code>--with-gssapi=[/path/to/krb5/root]</code> option to
2049 configure. For instance, I have all of my Kerberos V libraries
2050 installed under /usr/krb5 so I run <code>configure
2051 --with-gssapi=/usr/krb5</code></p>
2053 <p>Setting up Kerberos V authentication is beyond the scope of this
2054 FAQ (you may find Jim Rome's paper <a
2055 href="http://www.ornl.gov/~jar/HowToKerb.html">How to Kerberize
2056 your site</a> helpful), but you'll at least need to add a
2057 credential for imap/[mailhost] to the keytab of the mail server
2058 (IMAP doesn't just use the host key). Then you'll need to have your
2059 credentials ready on your machine (cf. kinit).</p>
2061 <p>After that things are very simple. Set your protocol to imap-gss
2062 in your .fetchmailrc, and omit the password, since imap-gss doesn't
2063 need one. You can specify a username if you want, but this is only
2064 useful if your mailbox belongs to a username different from your
2065 Kerberos principal.</p>
2067 <p>Now you don't have to worry about your password appearing in
2068 cleartext in your .fetchmailrc, or across the network.</p>
2070 <h2><a id="K5" name="K5">K5. How can I use fetchmail with
2073 <p>You'll need to have the <a
2074 href="http://www.openssl.org/">OpenSSL</a> libraries installed, and they
2075 should at least be version 0.9.6.
2076 Configure with --with-ssl. If you have the OpenSSL libraries
2077 installed in the default location (/usr/local/ssl) ths will
2078 suffice. If you have them installed in a non-default location,
2079 you'll need to specify it as an argument to --with-ssl after an
2082 <p>Fetchmail binaries built this way support <code>ssl</code>,
2083 <code>sslkey</code>, and <code>sslcert</code> options that control
2084 SSL encryption, and will automatically use <code>tls</code> if the
2085 server offers it. You will need to have an SSL-enabled mailserver to
2086 use these options. See the manual page for details and some words
2087 of care on the limited security provided.</p>
2089 <p>If your open OpenSSL session dies with a message that complains
2090 "PRNG not seeded", update or improve your operating system. This
2091 means that the OpenSSL library on your machine has been unable to
2092 locate a source of random bits from which to seed its random-number
2093 generator; normally these come from the <tt>/dev/urandom</tt>, and
2094 this message probably means your OS doesn't have that device.</p>
2096 <p>An interactive program could seed the random number generator
2097 from keystroke timings or some other form of user input. Because
2098 fetchmail is primarily designed to run forever as a background
2099 daemon, that option is not available in this case.</p>
2101 <p>If you don't have the libraries installed, but do have the
2102 OpenSSL utility toolkit, something like this may work (but will not
2103 authenticate the server):</p>
2106 poll MYSERVER port 993 plugin "openssl s_client -connect %h:%p"
2107 protocol imap username MYUSERNAME password MYPASSWORD
2110 <p>You should note that SSL is only secure against a "man-in-the-middle"
2111 attack if the client is able to verify that the peer's public key is the
2112 correct one, and has not been substituted by an attacker. fetchmail can do
2113 this in one of two ways: by verifying the SSL certificate, or by checking
2114 the fingerprint of the peer's public key.</p>
2116 <p>There are three parts to SSL certificate verification: checking that the
2117 domain name in the certificate matches the hostname you asked to connect to;
2118 checking that the certificate expiry date has not passed; and checking that
2119 the certificate has been signed by a known Certificate Authority (CA). This
2120 last step takes some preparation, as you need to install the root
2121 certificates of all the CA's which you might come across.</p>
2123 <p>The easiest way to do this is using the root CA keys supplied in the
2124 OpenSSL distribution, which means you need to download and unpack the
2125 source tarball from www.openssl.org. Once you have done that:</p>
2128 <li><code>mkdir /etc/ssl/certs</code></li>
2129 <li>in the openssl-x.x.x/certs directory: <code>cp *.pem /etc/ssl/certs/</code></li>
2130 <li>in the openssl-x.x.x/tools directory: edit c_rehash and set
2131 <code>$dir="/etc/ssl"</code></li>
2132 <li>run "perl c_rehash". This generates a number of symlinks within the
2133 /etc/ssl/certs/ directory</li>
2136 <p>Now in .fetchmailrc, set option sslcertpath to point to this
2140 poll pop3.example.com proto pop3 uidl no dns
2141 user foobar@example.com password xyzzy is foobar ssl sslcertpath /etc/ssl/certs
2144 <p>If the server certificate has not been signed by a known CA (e.g. it is a
2145 self-signed certificate), then this certificate validation will always
2148 <p>Certificate verification is always attempted. If it fails, by default a
2149 warning is printed but the connection carries on (which means you are not
2150 protected against attack). If your server's certificate has been properly
2151 set up and verifies correctly, then add the "sslcertck" option to enforce
2152 validation. If your server doesn't have a valid certificate though (e.g. it
2153 has a self-signed certificate) then it will never verify, and the only way
2154 you can protect yourself is by checking the fingerprint.</p>
2156 <p>To check the peer fingerprint: first use fetchmail -v once to connect to
2157 the host, at a time when you are pretty sure that there is no attack in
2158 progress (e.g. you are not traversing any untrusted network to reach the
2159 server). Make a note of the fingerprint shown. Now embed this in your
2160 .fetchmailrc using the sslfingerprint option: e.g.</p>
2163 poll pop3.example.com proto pop3 uidl no dns
2164 user foobar@example.com password xyzzy is foobar
2165 ssl sslfingerprint "67:3E:02:94:D3:5B:C3:16:86:71:37:01:B1:3B:BC:E2"
2168 <p>When you next connect, the public key presented by the server will be
2169 verified against the fingerprint given. If it's different, it may mean that
2170 a man-in-the-middle attack is in progress - or it might just mean that the
2171 server changed its key. It's up to you to determine which has happened.</p>
2173 <h2><a id="K6" name="K6">K6. How can I tell fetchmail not to use TLS
2174 if the server advertises it? Why does fetchmail use SSL even
2175 though not configured?</a></h2>
2177 <p>Some servers advertise STLS (POP3) or STARTTLS (IMAP), and fetchmail
2178 will automatically attempt TLS negotiation if SSL was enabled at compile
2179 time. This can however cause problems if the upstream didn't configure
2180 his certificates properly.</p>
2182 <p>In order to prevent fetchmail from trying TLS (STLS, STARTTLS)
2183 negotiation, add this option:</p>
2185 <pre>sslproto ssl23</pre>
2187 <p>This restricts fetchmail's SSL/TLS protocol choice from the default
2188 "SSLv2, SSLv3, TLSv1" to the two SSL variants, disabling TLSv1. Note
2189 however that this causes the connection to be unencrypted unless an
2190 encrypting "plugin" is used or SSL is requested explicitly.</p>
2193 <h1>Runtime fatal errors</h1>
2194 <h2><a id="R1" name="R1">R1. Fetchmail isn't working, and -v shows
2195 'SMTP connect failed' messages.</a></h2>
2197 <p>Fetchmail itself is probably working, but your SMTP port 25
2198 listener is down or inaccessible.</p>
2200 <p>The first thing to check is if you can telnet to port 25 on your
2201 smtp host (which is normally 'localhost' unless you've specified an
2202 smtp option in your .fetchmailrc or on the command line) and get a
2203 greeting line from the listener. If the SMTP host is inaccessible
2204 or the listener is down, fix that first.</p>
2206 <p>In Red Hat Linux 6.x, SMTP is disabled by default. To fix this,
2207 set "DAEMON=yes" in your /etc/sysconfig/sendmail file, then restart
2208 sendmail by running "/sbin/service sendmail restart".</p>
2210 <p>If the listener seems to be up when you test with telnet, the
2211 most benign and typical problem is that the listener had a
2212 momentary seizure due to resource exhaustion while fetchmail was
2213 polling it -- process table full or some other problem that stopped
2214 the listener process from forking. If your SMTP host is not
2215 'localhost' or something else in /etc/hosts, the fetchmail glitch
2216 could also have been caused by transient nameserver failure.</p>
2218 <p>Try running fetchmail -v again; if it succeeds, you had one of
2219 these kinds of transient glitch. You can ignore these hiccups,
2220 because a future fetchmail run will get the mail through.</p>
2222 <p>If the listener tests up, but you have chronic failures trying
2223 to connect to it anyway, your problem is more serious. One way to
2224 work around chronic SMTP connect problems is to use --mda. But this
2225 only attacks the symptom; you may have a DNS or TCP routing
2226 problem. You should really try to figure out what's going on
2227 underneath before it bites you some other way.</p>
2229 <p>We have one report (from toby@eskimo.com) that you can sometimes
2230 solve such problems by doing an <code>smtp</code> declaration with
2231 an IP address that your routing table maps to something other than
2232 the loopback device (he used ppp0).</p>
2234 <p>We also have a report that this error can be caused by having an
2235 /etc/hosts file that associates your client host name with more
2236 than one IP address.</p>
2238 <p>It's also possible that your DNS configuration isn't looking at
2239 <code>/etc/hosts</code> at all. If you're using libc5, look at
2240 <code>/etc/resolv.conf</code>; it should say something like:</p>
2246 <p>so your <code>/etc/hosts</code> file is checked first. If you're
2247 running GNU libc6, check your <code>/etc/nsswitch.conf</code> file.
2248 Make sure it says something like</p>
2254 <p>again, in order to make sure <code>/etc/hosts</code> is seen
2257 <p>If you have a hostname set for your machine, and this hostname
2258 does not appear in /etc/hosts, you will be able to telnet to port
2259 25 and even send a mail with rcpt to: user@host-not-in-/etc/hosts,
2260 but fetchmail can't seem to get in touch with sendmail, no matter
2261 what you set smtpaddress to.</p>
2263 <p>We had another report from a Linux user of fetchmail 2.1 who
2264 solved his SMTP connection problem by removing the reference to
2265 -lresolv from his link line and relinking. Apparently in some older
2266 Linux distributions the libc bind library version works better.</p>
2268 <p>As of 2.2, the configure script has been hacked so the bind
2269 library is linked only if it is actually needed. So under Linux it
2270 won't be, and this particular cause should go away.</p>
2272 <h2><a id="R2" name="R2">R2. When I try to configure an MDA,
2273 fetchmail doesn't work.</a></h2>
2275 <p>(I hear this one from people who have run into the blank-line
2276 problem in <a href="#X1">X1</a>.)</p>
2278 <p>Try sending yourself test mail and retrieving it using the
2279 command-line options '<code>-k -m cat</code>'. This will dump
2280 exactly what fetchmail retrieves to standard output (plus the
2281 Received line fetchmail itself adds to the headers).</p>
2283 <p>If the dump doesn't match what shows up in your mailbox when you
2284 configure an MDA, your MDA is mangling the message. If it doesn't
2285 match what you sent, then fetchmail or something on the server is
2288 <h2><a id="R3" name="R3">R3. Fetchmail dumps core when given an
2289 invalid rc file.</a></h2>
2291 <p>Note that this bug should no longer occur when using prepackaged
2292 fetchmail versions or installing unmodified original tarballs, since
2293 these ship with a proper parser .c file.</p>
2295 <p>This is usually reported from AIX or Ultrix, but has even been
2296 known to happen on Linuxes without a recent version of
2297 <code>flex</code> installed. The problem appears to be a result of
2298 building with an archaic version of lex.</p>
2300 <p>Workaround: fix the syntax of your .fetchmailrc file.</p>
2302 <p>Fix: build and install the latest version of <a
2303 href="http://flex.sourceforge.net/">flex</a>.</p>
2305 <h2><a id="R4" name="R4"><strike>R4. Fetchmail dumps core in -V mode, but
2306 operates normally otherwise.</strike></a></h2>
2308 <p><em>The information that used to be here referred to bugs in Linux libc5
2309 systems, which are deemed obsolete by now.</em></p>
2311 <h2><a id="R5" name="R5">R5. Running fetchmail in daemon mode
2312 doesn't work.</a><br/>
2315 <p>We have one report from a SunOS 4.1.4 user that trying to run
2316 fetchmail in detached daemon mode doesn't work, but that using the
2317 same options with -N (nodetach) is OK. We have another report of
2318 similar behavior from one Linux user, but many other Linux users
2319 report no problem.</p>
2321 <p>If this happens, you have a specific portability problem with
2322 the code in daemon.c that detaches and backgrounds the daemon
2323 fetchmail. The isolated Linux case has been chased down to a
2324 failure in dup(2) that may reflect a glibc bug.</p>
2326 <p>As a workaround, you can start fetchmail with -N and an
2327 ampersand to background it. A Sun user recommends this:</p>
2330 (fetchmail --nodetach <other params> &)
2333 <p>The extra pair of parens is significant --- it makes sure that
2334 the process detaches from the initial shell (one more shell is
2335 started and dies immediately, detaching fetchmail and making it
2336 child of PID 1). This is important when you start fetchmail
2337 interactively and than quit interactive shell. The line above makes
2338 sure fetchmail lives after that!</p>
2340 <h2><a id="R6" name="R6">R6. Fetchmail randomly dies with socket
2343 <p>Check the MTU value in your PPP interface reported by
2344 <code>/sbin/ifconfig</code>. If it's over 600, change it in your
2345 PPP options file. (<code>/etc/ppp/options</code> on my box). Here
2346 are option values that work:</p>
2353 <p>Another circumstance that can trigger this is if you are polling
2354 a virtual-mail-server name that is round-robin connected to
2355 different actual servers, so you get different IP addresses on
2356 different poll cycles. To work around this, change the poll name
2357 either to the real name of one of the servers in the ring or to a
2358 corresponding IP address.</p>
2360 <h2><a id="R7" name="R7">R7. Fetchmail running as root stopped
2361 working after an OS upgrade</a></h2>
2363 <p>In RH 6.0, the HOME value in the boot-time root environment
2364 changed from /root to / as the result of a change in init. Move
2365 your .fetchmailrc or use a -f option to explicitly point at the
2366 file. (Oddly, a similar problem has been reported from Debian
2369 <h2><a id="R8" name="R8">R8. Fetchmail is timing out after fetching
2370 certain messages but before deleting them</a></h2>
2372 <p>There's a TCP/IP stalling problem under Redhat 6.0 (and possibly
2373 other recent Linuxes) that can cause this symptom. Brian Boutel
2377 <p>TCP timestamps are turned on on my Linux boxes (I assume it's
2378 now the default). This uses 12 extra bytes per segment. When the
2379 tcp connection starts, the other end agrees a MSS of 1460, and then
2380 fragments 1460 byte chunks into 1448 and 12, because is is not
2381 allowing for the timestamp.</p>
2383 <p>Then, for reasons I can't explain, it waits a long time
2384 (typically 2 minutes) after the ack is sent before sending the next
2385 (fragmented) packet. Turning off tcp timestamps avoids the
2386 fragmentation and restores normal behaviour. To do this,
2389 <p>echo 0 > /proc/sys/net/ipv4/tcp_timestamps</p>
2391 <p>I'm still unclear about the details of why this is happening. At
2392 least [now] I am now getting good performance and no queue
2396 <h2><a id="R9" name="R9">R9. Fetchmail is timing out during message
2399 <p>This is probably a general networking issue. Sending a "RETR"
2400 command will cause the server to start sending large amounts of
2401 data, which means large packets. If your networking layer has a
2402 packet-fragmentation problem or improper firewall settings break Path
2403 MTU discovery (when for instance all ICMP traffic is blocked), that's
2404 where you'll see it.</p>
2406 <h2><a id="R10" name="R10"><strike>R10. Fetchmail is dying with
2407 SIGPIPE.</strike></a></h2>
2409 <p><em>Fetchmail 6.3.5 and newer block SIGPIPE, and many older versions have
2410 already handled this signal, so you shouldn't be seeing SIGPIPE
2413 <h2><a id="R11" name="R11">R11. My server is hanging or emitting
2414 errors on CAPA.</a></h2>
2416 <p>Your POP3 server is broken. You can work around this with the
2417 declaration <tt>auth password</tt> in your .fetchmailrc.</p>
2419 <h2><a id="R12" name="R12">R12. Fetchmail isn't working and reports
2420 getaddrinfo errors.</a></h2>
2421 <ol><li>Make sure you haven't mistyped the host name or address, and that
2422 your DNS is working. If you cannot fix DNS, give the numeric host
2423 literal, for instance, 192.168.0.1</li>
2424 <li>Make sure your <code>/etc/services</code> file (or other
2425 services database) contains the necessary service entries. If you
2426 cannot fix the services database, use the --service option and give the
2427 numeric port address. Common port addresses are:<table
2428 summary="Common port addresses for IMAP, POP3 and their SSL
2430 <tr><th>service</th><th>port</th></tr>
2431 <tr><td>IMAP</td><td>143</td></tr>
2432 <tr><td>IMAP+SSL</td><td>993</td></tr>
2433 <tr><td>POP3</td><td>110</td></tr>
2434 <tr><td>POP3+SSL</td><td>995</td></tr>
2437 <h2><a id="R13" name="R13">R13. What does "Interrupted system call"
2440 <p>Non-fatal signals (such as timers set by fetchmail itself) can
2441 interrupt long-running functions and will then be reported as
2442 "Interrupted system call". These can sometimes be timeouts.</p>
2445 <h1>Hangs and lockups</h1>
2446 <h2><a id="H1" name="H1">H1. Fetchmail hangs when used with
2449 <p>Your problem may be with pppd's 'demand' option. We have a
2450 report that fetchmail doesn't play well with it, but works with
2451 pppd if 'demand' is turned off. We have no idea why this is.</p>
2453 <h2><a id="H2" name="H2">H2. Fetchmail hangs during the MAIL FROM
2456 <p>The symptom: 'fetchmail -v' retrieves mail fine, but appears to
2457 hang after sending the MAIL FROM command</p>
2460 SMTP> MAIL FROM: <someone@somewhere>
2463 <p>The hang is actually occuring when sendmail looks up a sender's
2464 address in DNS. The problem isn't in fetchmail but in the
2465 configuration of sendmail. You must enable the 'nodns' and
2466 'nocanonify' features of sendmail.</p>
2468 <p>Here was my fix for RedHat 7.2:</p>
2471 <li># cd /etc/mail</li>
2473 <li># cp sendmail.mc sendmail-mine.mc</li>
2475 <li>Edit sendmail-mine.mc and add lines:
2483 <li>Build a new sendmail.cf
2486 # m4 sendmail-mine.cf > /etc/sendmail.cf
2490 <li>Restart sendmail.</li>
2493 <p>For more details consult the file
2494 /usr/share/sendmail-cf/README.</p>
2496 <h2><a id="H3" name="H3">H3. Fetchmail hangs while fetching
2499 <p>The symption: 'fetchmail -v' retrieves the first few messages,
2500 but hangs returning:</p>
2503 fetchmail: SMTP< 550 5.0.0 Access denied
2504 fetchmail: SMTP> RSET
2505 fetchmail: SMTP< 250 2.0.0 Reset state
2506 .......fetchmail: flushed
2507 fetchmail: POP3> DELE 1
2508 fetchmail: POP3< +OK marked deleted
2511 <p>Check and see if you're allowing sendmail connections through
2514 <p>Adding 'sendmail : 127.0.0.1' to /etc/hosts.allow could solve
2518 <h1>Disappearing mail</h1>
2519 <h2><a id="D1" name="D1">D1. I think I've set up fetchmail
2520 correctly, but I'm not getting any mail.</a></h2>
2522 <p>Maybe you have a .forward or alias set up that you've forgotten
2523 about. You should probably remove it.</p>
2525 <p>Or maybe you're trying to run fetchmail in multidrop mode as
2526 root without a .fetchmailrc file. This doesn't do what you think it
2527 should; see question <a href="#C1">C1</a>.</p>
2529 <p>Or you may not be connecting to the SMTP listener. Run fetchmail
2530 -v and see <a href="#R1">R1</a>.</p>
2532 <p>Or you may have your local user set incorrectly. In the
2536 user 'remoteuser' there with password '*' is 'localuser' here
2539 <p>make sure that 'localuser' does exist and can receive mail.</p>
2541 <h2><a id="D2" name="D2">D2. All my mail seems to disappear after a
2542 dropped connection.</a></h2>
2544 <p>One POP3 daemon used in the Berkeley Unix world that reports
2545 itself as POP3 version 1.004 actually throws the queue away. 1.005
2546 fixed that. If you're running this one, upgrade immediately. (It
2547 also truncates long lines at column 1024.)</p>
2549 <p>Many POP servers, if an interruption occurs, will restore the
2550 whole mail queue after about 10 minutes. Better ones will restore it
2551 right away. If you have an interruption and don't see it right
2552 away, cross your fingers and wait ten minutes before retrying.</p>
2554 <p>Good servers are designed to restore the entire queue, including
2555 messages you have deleted. If you have one of these and it flakes out on
2556 you a lot, try setting a small <code>--fetchlimit</code> value. This
2557 will result in more IP connects to the server, but will mean it actually
2558 executes changes to the queue more often.</p>
2560 <h2><a id="D3" name="D3">D3. Mail that was being fetched when I
2561 interrupted my fetchmail seems to have been vanished.</a></h2>
2563 <p>Fetchmail only sends a delete mail request to the server when
2564 either (a) it gets a positive delivery acknowledgment from the SMTP
2565 listener, or (b) it gets one of the spam-filter errors (see the
2566 description of the <code>antispam></code> option) from the
2567 listener. No interrupt can cause it to lose mail.</p>
2569 <p>However, IMAP2bis has a design problem in that its normal fetch
2570 command marks a message 'seen' as soon as the fetch command to get
2571 it is sent down. If for some reason the message isn't actually
2572 delivered (you take a line hit during the download, or your port 25
2573 listener can't find enough free disk space, or you interrupt the
2574 delivery in mid-message) that 'seen' message can lurk invisibly in
2575 your server mailbox forever.</p>
2577 <p>Workaround: add the '<code>fetchall</code>' keyword to your
2580 <p>Solution: switch to an <a href="http://www.imap.org/">IMAP4</a>
2584 <h1>Multidrop-mode problems</h1>
2585 <h2><a id="M1" name="M1">M1. I've declared local names, but all my
2586 multidrop mail is going to root anyway.</a></h2>
2588 <p>Somehow your fetchmail is never recognizing the hostname part of
2589 recipient names it parses out of Envelope-header lines (or these are
2590 improperly configured) as
2591 matching a name within the designated domains. To check this, run
2592 fetchmail in foreground with -v -v on. You will probably see a lot
2593 of messages with the format "line rejected, %s is not an alias of
2594 the mailserver" or "no address matches; forwarding to %s."</p>
2596 <p>These errors usually indicate some kind of configuration
2599 <p>The easiest workaround is to add a '<code>via</code>' option (if
2600 necessary) and add enough '<code>aka</code>' declarations to cover all
2601 of your mailserver's aliases, then say '<code>no dns</code>'. This will
2602 take DNS out of the picture (though it means mail may be uncollected if
2603 it's sent to an alias of the mailserver that you don't have listed).</p>
2605 <p>Occasionally these errors indicate the sort of header-parsing
2606 problem described in <a href="#M7">M7</a>.</p>
2608 <h2><a id="M2" name="M2">M2. I can't seem to get fetchmail to route
2609 to a local domain properly.</a></h2>
2611 <p>A lot of people want to use fetchmail as a poor man's
2612 internetwork mail gateway, picking up mail accumulated for a whole
2613 domain in a single server mailbox and then routing based on what's
2614 in the To/Cc/Bcc lines.</p>
2616 <p>In general, this is not really a good idea. It would be smarter
2617 to just let the mail sit in the mailserver's queue and use
2618 fetchmail's ETRN or ODMR modes to trigger SMTP sends periodically
2619 (of course, this means you have to poll more frequently than the
2620 mailserver's expiration period). If you can't arrange this, try
2621 setting up a UUCP feed.</p>
2623 <p>If neither of these alternatives is available, multidrop mode
2624 may do (though you <em>are</em> going to get hurt by some mailing
2625 list software; see the caveats under THE USE AND ABUSE OF MULTIDROP
2626 MAILBOXES on the man page, and check what is needed at <a
2627 href="http://home.pages.de/~mandree/mail/multidrop">Matthias
2628 Andree's "Requisites for working multidrop
2629 mailboxes"</a>). If you want to try it, the way to do it is
2630 with the '<code>localdomains</code>' option.</p>
2632 <p>In general, if you use localdomains you need to make sure of two
2635 <p><strong>1. You've actually set up your .fetchmailrc entry to
2636 invoke multidrop mode.</strong></p>
2638 <p>Many people set a '<code>localdomains</code>' list and then
2639 forget that fetchmail wants to see more than one name (or the
2640 wildcard '*') in a '<code>here</code>' list before it will do
2641 multidrop routing.</p>
2643 <p><strong>2. You may have to set 'no envelope'.</strong></p>
2645 <p>Normally, multidrop mode tries to deduce an envelope address
2646 from a message before parsing the To/Cc/Bcc lines (this enables it
2647 to avoid losing to mailing list software that doesn't put a
2648 recipient address in the To lines).</p>
2650 <p>Some ways of accumulating a whole domain's messages in a single
2651 server mailbox mean it all ends up with a single envelope address
2652 that is useless for rerouting purposes. In this particular case, sell
2653 your ISP a clue. If that does not work, you may have to set
2654 '<code>no envelope</code>' to prevent fetchmail from being
2655 bamboozled by this, but a missing envelope makes multidrop routing
2658 <p>Check also answer <a href="#T1">T1</a> on a reliable way to do
2659 multidrop delivery if your ISP (or your mail redirection provider)
2662 <h2><a id="M3" name="M3">M3. I tried to run a mailing list using
2663 multidrop, and I have a mail loop!</a></h2>
2665 <p>This isn't fetchmail's fault. Check your mailing list. If the
2666 list expansion includes yourself or anybody else at your mailserver
2667 (that is, not on the client side) you've created a mail loop. Just
2668 chop the host part off any local addresses in the list.</p>
2670 <p>If you use sendmail, you can check the list expansion with
2671 <code>sendmail -bv</code>.</p>
2673 <h2><a id="M4" name="M4"><strike>M4. My multidrop fetchmail seems to be
2674 having DNS problems.</strike></a></h2>
2676 <p>The answer that used to be here no longer applies to fetchmail.</p>
2678 <h2><a id="M5" name="M5">M5. I'm seeing long DNS delays before each
2679 message is processed.</a></h2>
2681 <p>Use the '<code>aka</code>' option to pre-declare as many of your
2682 mailserver's DNS names as you can. When an address's host part
2683 matches an aka name, no DNS lookup needs to be done to check
2686 <p>If you're sure you've pre-declared all of your mailserver's DNS
2687 names, you can use the '<code>no dns</code>' option to prevent
2688 other hostname parts from being looked up at all.</p>
2690 <p>Sometimes delays are unavoidable. Some SMTP listeners try to
2691 call DNS on the From-address hostname as a way of checking that the
2692 address is valid.</p>
2694 <h2><a id="M6" name="M6">M6. How do I get multidrop mode to work
2695 with majordomo?</a></h2>
2697 <p>In order for sendmail to execute the command strings in the
2698 majordomo alias file, it is necessary for sendmail to think that
2699 the mail it receives via SMTP really is destined for a local user
2700 name. A normal virtual-domain setup results in delivery to the
2701 default mailbox, rather than expansion through majordomo.</p>
2703 <p>Michael <michael@bizsystems.com> gave us a recipe for
2704 dealing with this case that pairs a run control file like this:</p>
2707 poll your.pop3.server proto pop3:
2709 localdomains virtual.localdomain1.com virtual.localdomain2.com ...
2710 user yourISPusername is root * here,
2711 password yourISPpassword fetchall
2714 <p>with a hack on your local sendmail.cf like this:</p>
2717 #############################################
2718 # virtual info, local hack for ruleset 98 #
2719 #############################################
2721 # domains to treat as direct mapped local domain
2723 CVvirtual.localdomain1.com virtual.localdomain2.com ...
2724 ---------------------------
2726 -------------------------
2727 # handle virtual users
2729 R$+ <@ $=V . > $: $1 < @ $j . >
2730 R< @ > $+ < @ $=V . > $: $1 < @ $j . >
2731 R< @ > $+ $: $1
2732 R< error : $- $+ > $* $#error $@ $1 $: $2
2733 R< $+ > $+ < @ $+ > $: $>97 $1
2736 <p>This ruleset just strips virtual domain names off the addresses
2737 of incoming mail. Your sendmail must be 8.8 or newer for this to
2738 work. Michael says:</p>
2740 <blockquote>I use this scheme with 2 virtual domains and the
2741 default ISP user+domain and service about 30 mail accounts +
2742 majordomo on my inside pop3 server with fetchmail and sendmail
2745 <h2><a id="M7" name="M7">M7. Multidrop mode isn't parsing envelope
2746 addresses from my Received headers as it should.</a></h2>
2748 <p>It may happen that you're getting what appear to be well-formed
2749 sendmail Received headers, but fetchmail can't seem to extract an
2750 envelope address from them. There can be a couple of reasons for
2753 <h3>Spurious Received lines need to be skipped:</h3>
2755 <p>First, fetchmail might be looking at the wrong Received header.
2756 Normally it looks only on the first one it sees, on the theory that
2757 that one was last added and is going to be the one containing your
2758 mailserver's theory of who the message was addressed to.</p>
2760 <p>Some (unusual) mailserver configurations will generate extra
2761 Received lines which you need to skip. To arrange this, use the
2762 optional skip prefix argument of the 'envelope' option; you may
2763 need to say something like '<code>envelope 1 Received</code>' or
2764 '<code>envelope 2 Received</code>'.</p>
2766 <h3>The 'by' clause doesn't contain a mailserver alias:</h3>
2768 <p>When fetchmail parses a Received line that looks like</p>
2771 Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
2772 by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
2773 for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
2776 <p>it checks to see if 'iserv.ttns.net' is a DNS alias of your
2777 mailserver before accepting 'ksturgeon@fbceg.org' as an envelope
2778 address. This check might fail if your DNS were misconfigured, or
2779 if you were using 'no dns' and had failed to declare iserv.ttns.net
2780 as an alias of your server.</p>
2782 <h2><a id="M8" name="M8">M8. Users are getting multiple copies of
2785 <p>It's a consequence of multidrop. What's happening is that you
2786 have N users subscribed to the same list. The list software sends N
2787 copies, not knowing they will end up in the same multidrop box.
2788 Since they are both locally addressed to all N users, fetchmail
2789 delivers N copies to each user.</p>
2791 <p>Fetchmail tries to eliminate adjacent duplicate messages in a
2792 multidrop mailbox. However, this logic depends on the message-ID
2793 being identical in both copies. It also depends on the two copies
2794 being adjacent in the server mailbox. The former is usually the
2795 case, but the latter condition sometimes fails in a
2796 timing-dependent way if the server was processing multiple incoming
2799 <p>I could eliminate this problem by keeping a list of all
2800 message-IDs received during a poll so far and dropping any message
2801 that matches a seen mail ID. The trouble is that this is an O(N**2)
2802 operation that might significantly slow down the retrieval of large
2805 <p>The real solution however is to make sure that fetchmail can find the
2806 envelope recipient properly, which will reliably prevent this message
2810 <h1>Mangled mail</h1>
2811 <h2><a id="X1" name="X1">X1. Spurious blank lines are appearing in
2812 the headers of fetched mail.</a></h2>
2814 <p>What's probably happening is that the POP/IMAP daemon on your
2815 mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
2816 something in your delivery path (most likely an old version of the
2817 <em>deliver</em> program, which sendmail often calls to do local
2818 delivery) is failing to recognize it as a header.</p>
2820 <p>This is not fetchmail's problem. The first thing to try is
2821 installing a current version of <em>deliver</em>. If this doesn't
2822 work, try to figure out which other program in your mail path is
2823 inserting the blank line and replace that. If you can't do either
2824 of these things, pick a different MDA (such as maildrop) and
2825 declare it with the '<code>mda</code>' option.</p>
2827 <h2><a id="X2" name="X2">X2. My mail client can't see a Subject
2830 <p>First, see <a href="#X1">X1</a>. This is quite probably the same
2831 problem (X-POP3-Rcpt header or something similar being inserted by
2832 the server and choked on by an old version of
2833 <em>deliver</em>).</p>
2835 <p>The O'Reilly sendmail book does warn that IDA sendmail doesn't
2836 process X- headers correctly. If this is your problem, all I can
2837 suggest is replacing IDA sendmail, because it's broken and not
2838 RFC822 conformant.</p>
2840 <h2><a id="X3" name="X3">X3. Messages containing "From" at the start of
2841 line are being split.</a></h2>
2843 <p>If you know the messages aren't split in your server mailbox,
2844 then this is a problem with your POP/IMAP server, your client-side
2845 SMTP listener or your local delivery agent. Fetchmail cannot split
2848 <p>Some POP server daemons ignore Content-Length headers and split
2849 messages on From lines. We have one report that the 2.1 version of
2850 the BSD popper program (as distributed on Solaris 2.5 and
2851 elsewhere) is broken this way.</p>
2853 <p>You can test this. Declare an mda of 'cat' and send yourself one
2854 piece of mail containing "From" at start of a line. If you see a
2855 split message, your POP/IMAP server is at fault. Upgrade to a more
2858 <p>Sendmail and other SMTP listeners don't split RFC822 messages
2859 either. What's probably happening is either sendmail's local
2860 delivery agent or your mail reader are not quite RFC822-conformant
2861 and are breaking messages on what it thinks are Unix-style From
2862 headers. You can figure out which by looking at your client-side
2863 mailbox with vi or more. If the message is already split in your
2864 mailbox, your local delivery agent is the problem. If it's not,
2865 your mailreader is the problem.</p>
2867 <p>If you can't replace the offending program, take a look at your
2868 sendmail.cf file. There will likely be a line something like</p>
2871 Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
2874 <p>describing your local delivery agent. Try inserting the 'E'
2875 option in the flags part (the F= string). This will make sendmail
2876 turn each dangerous start-of-line From into a >From, preventing
2877 programs further downstream from acting up.</p>
2879 <h2><a id="X4" name="X4">X4.</a> <a id="generic_mangling"
2880 name="generic_mangling">My mail is being mangled in a new and
2881 different way</a></h2>
2883 <p>The first thing you need to do is pin down what program is doing
2884 the mangling. We don't like getting bug reports about fetchmail
2885 that are actually due to some other program's malfeasance, so
2886 please go through this diagnostic sequence before sending us a
2889 <p>There are five possible culprits to consider, listed here in the
2890 order they pass your mail:</p>
2893 <li>Programs upstream of your server mailbox.</li>
2895 <li>The POP or IMAP server on your mailserver host.</li>
2897 <li>The fetchmail program itself.</li>
2899 <li>Your local sendmail.</li>
2901 <li>Your LDA (local delivery agent), as called by sendmail or
2902 specified by <code>mda</code>.</li>
2905 <p>Often it happens that fetchmail itself is OK, but using it
2906 exposes pre-existing bugs in your downstream software, or your
2907 downstream software has a bad interaction with POP/IMAP. You need
2908 to pin down exactly where the message is being garbled in order to
2909 deduce what is actually going on.</p>
2911 <p>The first thing to do is send yourself a test message, and
2912 retrieve it with a .fetchmailrc entry containing the following (or
2913 by running with the equivalent command-line options):</p>
2916 mda "cat >MBOX" keep fetchall
2919 <p>This will capture what fetchmail gets from the server, except
2920 for (a) the extra Received header line fetchmail prepends, (b)
2921 header address changes due to <code>rewrite</code>, and (c) any
2922 end-of-line changes due to the <code>forcecr</code> and
2923 <code>stripcr</code> options. MBOX will in fact contain what
2924 programs downstream of fetchmail see.</p>
2926 <p>The most common causes of mangling are bugs and
2927 misconfigurations in those downstream programs. If MBOX looks
2928 unmangled, you will know that is what is going on and that it is
2929 not fetchmail's problem. Take a look at the other FAQ items in this
2930 section for possible clues about how to fix your problem.</p>
2932 <p>If MBOX looks mangled, the next thing to do is compare it with
2933 your actual server mailbox (if possible). That's why you specified
2934 <code>keep</code>, so the server copy would not be deleted. If your
2935 server mailbox looks mangled, programs upstream of your server
2936 mailbox are at fault. Unfortunately there is probably little you
2937 can do about this aside from complaining to your site postmaster,
2938 and nothing at all fetchmail can do about it!</p>
2940 <p>More likely you'll find that the server copy looks OK. In that
2941 case either the POP/IMAP server or fetchmail is doing the mangling.
2942 To determine which, you'll need to telnet to the server port and
2943 simulate a fetchmail session yourself. This is not actually hard
2944 (both POP3 and IMAP are simple, text-only, line-oriented protocols)
2945 but requires some attention to detail. You should be able to use a
2946 fetchmail -v log as a model for a session, but remember that the
2947 "*" in your LOGIN or PASS command dump has to be replaced with your
2948 actual password.</p>
2950 <p>The objective of manually simulating fetchmail is so you can see
2951 exactly what fetchmail sees. If you see a mangled message, then
2952 your server is at fault, and you probably need to complain to your
2953 mailserver administrators. However, we like to know what the broken
2954 servers are so we can warn people away from them. So please send us
2955 a transcript of the session including the mangling <em>and the
2956 server's initial greeting line</em>. Please tell us anything else
2957 you think might be useful about the server, like the server host's
2958 operating system.</p>
2960 <p>If your manual fetchmail simulation shows an unmangled message,
2961 congratulations. You've found an actual fetchmail bug, which is a
2962 pretty rare thing these days. Complain to us and we'll fix it.
2963 Please include the session transcript of your manual fetchmail
2964 simulation along with the other things described in the FAQ entry
2965 on <a href="#G3">reporting bugs</a>.</p>
2967 <h2><a id="X5" name="X5"><strike>X5. Using POP3, retrievals seems to be
2968 fetching too much!</strike></a></h2>
2970 <p>The information that used to be here pertained to fetchmail 4.4.7 or
2971 older, which should not be used. Use a recent fetchmail version.</p>
2973 <p>Workaround: set the <code>fetchall</code> option. Under POP3
2974 this has the side effect of forcing RETR use.</p>
2976 <h2><a id="X6" name="X6">X6. My mail attachments are being dropped
2977 or mangled.</a></h2>
2979 <p>Fetchmail doesn't discard attachments; fetchmail doesn't have any idea
2980 that attachments are there. Fetchmail treats the body of each message as
2981 an uninterpreted byte stream and passes it through without alteration.
2982 If you are not receiving attachments through fetchmail, it is because
2983 your mailserver is not sending them to you.</p>
2985 <p>The fix for this is to replace your mailserver with one that works.
2986 If its operating system makes this difficult, you should replace its
2987 operating system with one that works. Windows- and NT-based POP servers
2988 seem especially prone to mangle attachments. If you are running one
2989 of these, replacing your server with a Unix machine is probably the
2990 only effective solution.</p>
2992 <p>We've had sporadic reports of problems with Microsoft Exchange and
2993 Outlook servers. These sometimes randomly fail to ship
2994 attachments to your client. This is a known bug, acknowledged by
2997 <p>They may also mangle the attachments they do pass through. If you
2998 see unreadable attachments with a ContentType of "application/x-tnef",
2999 you're having this problem. The <a
3000 href="http://world.std.com/~damned/software.html">TNEF</a> utility may
3003 <p>The Mail Max POP3 server and the InterChange and Imail IMAP
3004 servers are known to simply drop MIME attachments when uploading
3007 <p>We've also had a report that Lotus Notes sometimes trashes the
3008 MIME type of messages. In particular, it seems to modify MIME
3009 headers of type application/pdf, mangling the type to
3010 application/octet-stream. It may corrupt other MIME types as
3013 <p>The IMAP service of Lotus Domino has a known bug in the way it
3014 generates MIME Content-type headers (observed on Lotus Domino
3015 5.0.2b). It's a subtle one that doesn't show up when Netscape
3016 Messenger and other clients use a FETCH BODY[] to grab the whole
3017 message. When fetchmail uses FETCH RFC822.HEADER and FETCH
3018 RFC822.TEXT to get first the header and then the body, Domino
3019 generates different Boundary tags for each part, e.g. one tag is
3020 declared in the Content-type header and another is used to separate
3021 the MIME parts in the body. This doesn't work. (I have heard a
3022 rumor that this bug is scheduled to be fixed in Domino release 6;
3023 you can find a workaround at contrib/domino.)</p>
3025 <p>Rob Funk explains: Unfortunately there also remain many mail
3026 user agents that don't write correct MIME messages. One big
3027 offender is Sun MailTool attachments, which are formatted enough
3028 like MIME that some programs could get confused; these are
3029 generated by the mailtool and dtmail programs (the mail programs in
3030 Sun's OpenWindows and CDE environments).</p>
3032 <p>One solution to problems related to misformatted MIME
3033 attachments is the <a
3034 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/">emil</a>
3036 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/TUTORIAL.html">tutorial</a>
3037 file at that site for details on emil. It is useful for converting
3038 character sets, attachment encodings, and attachment formats. At
3039 this writing, emil does not appear to have been maintained since a
3040 patch to version 2.1.0beta9 in late 1997, but it is still
3043 <p>One good way of using emil is from within procmail. You can have
3044 procmail look for signs of problematic message formatting, and pipe
3045 those messages through emil to be fixed. emil will not always be
3046 able to fix the problem, in which case the message is
3049 <p>A possible rule to be inserted into a .procmailrc file for using
3054 * 1^1 ^Content-Type: \/X-sun[^;]*
3055 * 1^1 ^Content-Type: \/application/mac-binhex[^;]*
3056 * 1^1 ^Content-Transfer-Encoding: \/x-binhex[^;]*
3057 * 1^1 ^Content-Transfer-Encoding: \/x-uuencode[^;]*
3059 LOG="Converting $MATCH
3062 | emil -A B -T Q -B BA -C iso-8859-1 -H Q -F MIME \
3063 | gawk '{gsub(/\r\n?/,"\n");print $0}'
3067 <p>The "1^1" in the conditions is a way of specifying to procmail
3068 that if any one of the four listed expressions is found in the
3069 message, the total condition is considered true, and the message
3070 gets passed into emil. These four subconditions check whether the
3071 message has a Sun attachment, a binhex attachment, or a uuencoded
3072 attachment; there are others that could be added to check these
3073 things better and to check other relevant conditions. The "LOG="
3074 line writes a line into the procmail log; the lone double-quote
3075 beginning the following line makes sure the log entry gets an
3076 end-of-line character. The call to gawk (GNU awk) is for fixing
3077 end-of-line conventions, since emil sometimes leaves those in the
3078 format of the originating machine; it could probably be replaced
3079 with a sed subsitution.</p>
3081 <p>The emil call itself tries to ensure that the message uses:</p>
3084 <li>BinHex encoding for any Apple Macintosh-only attachments</li>
3086 <li>Quoted-Printable encoding for text (when necessary)</li>
3088 <li>Base64 Encoding for binary attachments</li>
3090 <li>iso-8859-1 character set for text (unfortunately emil can't yet
3091 convert from windows-1252 to iso-8859-1)</li>
3093 <li>Quoted-Printable encoding for headers</li>
3095 <li>MIME attachment format</li>
3098 <p>Most of these (the primary exceptions being the character set
3099 and the Apple binary format) are as they should be for good
3100 internet interoperability.</p>
3102 <p>Some mail servers (Lotus Domino is a suspect here) mangle
3103 Sun-formatted messages, so the conversion to MIME needs to happen
3104 before such programs see the message. The ideal is to rid the world
3105 of Sun-formatted messages: don't use mailtool for sending
3106 attachments (it doesn't understand MIME anyway, and most of the
3107 world doesn't understand its attachments, so it really shouldn't be
3108 used at all), and make sure dtmail is set to use MIME rather than
3109 mailtool's format.</p>
3111 <h2><a id="X7" name="X7">X7. Some mail attachments are hanging
3114 <p>This isn't fetchmail's problem either; fetchmail doesn't know
3115 anything about mail attachments and doesn't treat them any
3116 differently from plain message data.</p>
3118 <p>The most usual cause of this problem seems to be bugs in your
3119 network transport layer's capability to handle the very large
3120 TCP/IP packets that attachments tend to turn into. You can test
3121 this theory by trying to download the offending message through a
3122 webmail account; using HTTP for the message tends to simulate
3123 large-packet stress rather well, and you will probably find that
3124 the messages that seem to be choking fetchmail will make your HTTP
3125 download speed drop to zero.</p>
3127 <p>This problem can be caused by subtle bugs in the
3128 packet-reassembly layer of your TCP/IP stack; these often don't
3129 manifest at normal packet sizes. It may also be caused by
3130 malfunctioning path-MTU discovery on the mailserver. Or, if there's
3131 a modem in the link, it may be because the attachment contains the
3132 Hayes mode escape "+++".</p>
3134 <h2><a id="X8" name="X8">X8. A spurious ) is being appended to my
3137 <p>Blame it on that rancid pile of dung and offal called Microsoft
3138 Exchange. Due to the problem described in <a href="#S2">S2</a>, the
3139 IMAP support in fetchmail cannot follow the IMAP protocol 100%.
3140 Most of the time it doesn't matter, but if you combine it with an
3141 SMTP server that behaves unusually, you'll get a spurious ) at
3144 <p>One piece of software that can trigger this is the Interchange
3145 mail server, as used by, e.g., mailandnews.com. Here's what
3148 <p>1. Someone sends mail to your account. The last line of the
3149 message contains text. So at the SMTP level, the message ends with,
3150 e.g. "blahblah\r\n.\r\n"</p>
3152 <p>2. The SMTP handler sees the final "\r\n.\r\n" and recognizes
3153 the end of the message. However, instead of doing the normal thing,
3154 which is tossing out the ".\r\n" and leaving the first '\r\n' as
3155 part of the email body, Interchange throws out the whole
3156 "\r\n.\r\n", and leaves the email body without any line terminator
3157 at the end of it. RFC821 does not forbid this, though it probably
3160 <p>3. Fetchmail, or some other IMAP client, asks for the message.
3161 IMAP returns it, but it's enclosed inside parentheses, according to
3162 the protocol. The message size in bytes is also present. Because
3163 the message doesn't end with a line terminator, the IMAP client
3171 <p>where the ')' is from IMAP.</p>
3173 <p>4. Fetchmail only deals with complete lines, and can't trust the
3174 stated message size because Microsoft Exchange fscks it up.</p>
3176 <p>5. As a result, fetchmail takes the final 'blahblah)' and puts
3177 it at the end of the message it forwards on. If you have verbosity
3178 on, you'll get a message about actual != expected.</p>
3180 <p>There is no fix for this. The nuke mentioned in <a
3181 href="#S2">S2</a> looks more tempting all the time.</p>
3183 <h2><a id="X9" name="X9">X9. Missing "Content-Transfer-Encoding" header
3184 with Domino IMAP</a></h2>
3186 <p>Domino 6 IMAP was found by Anthony Kim in February 2006 to
3187 erroneously omit the "Content-Transfer-Encoding" header in messages
3188 downloaded through IMAP, causing messages to display improperly. This
3189 happened with Domino's incoming mail format configured to "Prefers
3190 MIME". Solution: switch Domino to "Keep in Sender's format".</p>
3193 href="http://lists.ccil.org/pipermail/fetchmail-friends/2006-March/010015.html">Anthony
3198 <h1>Other problems</h1>
3199 <h2><a id="O1" name="O1">O1. The --logfile option doesn't work if
3200 the logfile doesn't exist.</a></h2>
3202 <p>This is a feature, not a bug. It's in line with normal practice
3203 for system daemons and allows you to suppress logging by removing
3204 the log file, without hacking potentially fragile startup scripts.
3205 To get around it, just touch(1) the logfile before you run fetchmail
3206 (this will have no effect on the contents of the logfile if it already
3209 <h2><a id="O2" name="O2">O2. Every time I get a POP or IMAP message,
3210 the header is dumped to all my terminal sessions.</a></h2>
3212 <p>Fetchmail uses the local sendmail to perform final delivery,
3213 which Mozilla and other clients don't do; the announcement of
3214 new messages is done by a daemon that sendmail pokes. There should
3215 be a "biff" command to control this. Type</p>
3221 <p>to turn it off. If this doesn't work, try the command</p>
3227 <p>which is essentially what <code>biff -n</code> will do. If this
3228 doesn't work, comment out any reference to "comsat" in your
3229 /etc/inetd.conf file and reload (or restart) inetd.</p>
3231 <p>In Slackware Linux distributions, the last line in /etc/profile
3244 to solve the problem system-wide.
3246 <h2><a id="O3" name="O3">O3. Does fetchmail reread its rc file
3247 every poll cycle?</a></h2>
3249 <p>No, but versions 5.2.2 and later will notice when you modify
3250 your rc file and restart, reading it. Note that this causes troubles if
3251 you need to provide a password via the console, unless you're running in
3252 --nodetach mode.</p>
3254 <h2><a id="O4" name="O4">O4. Why do deleted messages show up again
3255 when I take a line hit while downloading?</a></h2>
3257 <p>According to the POP3 RFCs, deletes aren't actually performed
3258 until you issue the end-of-session QUIT command. Fetchmail cannot
3259 fix this, but there is a workaround: use the --expunge option with a
3260 reasonably low figure that works for you. Try 10 for a start.</p>
3262 <p>IMAP is less susceptible to this problem, because the "deleted"
3263 message marks are persistent, but they aren't in POP3. Note that the
3264 --expunge default for IMAP is different than the default for POP3.</p>
3266 <p>If you get very unlucky, you might take a line hit in the window
3267 between the delete and the expunge. If you've set a longer expunge
3268 interval, the window gets wider. This problem should correct itself
3269 the next time you complete a successful query.</p>
3271 <h2><a id="O5" name="O5">O5. Why is fetched mail being logged with
3272 my name, not the real From address?</a></h2>
3274 <p>Because logging is done based on the address indicated by the
3275 sending SMTP's MAIL FROM, and some listeners are picky about that
3278 <p>Some SMTP listeners get upset if you try to hand them a MAIL
3279 FROM address naming a different host than the originating site for
3280 your connection. This is a feature, not a bug -- it's supposed to
3281 help prevent people from forging mail with a bogus origin site.
3282 (RFC 1123 says you shouldn't do this exclusion...)</p>
3284 <p>Since the originating site of a fetchmail delivery connection is
3285 localhost, this effectively means these picky listeners will barf
3286 on any MAIL FROM address fetchmail hands them with an @ in it!</p>
3288 <p>Versions 2.1 and up try the header From address first and fall
3289 back to the calling-user ID. So if your SMTP listener isn't picky,
3290 the log will look right.</p>
3292 <h2><a id="O6" name="O6">O6. I'm seeing long sendmail delays or
3293 hangs near the start of each poll cycle.</a></h2>
3295 <p>Sendmail does a hostname lookup when it first starts up, and
3296 also each time it gets a HELO in listener mode.</p>
3298 <p>Your resolver configuration may be causing one of these lookups
3299 to fail and time out. Check your <code>/etc/resolv.conf</code>,
3300 <code>/etc/host.conf</code>, <code>/etc/nsswitch.conf</code> (if you
3301 have the latter two) and you <code>/etc/hosts</code> files. Make sure
3302 your hostname and fully-qualified domain name are both in
3303 <code>/etc/hosts</code>, and that hosts is looked at before DNS is
3304 queried. You probably also want your remote mail server(s) to be in the
3307 <p>You can suppress the startup-time lookup if need to by reconfiguring
3308 with <code>FEATURE(nodns)</code>.</p>
3310 <p>Configuring your bind library to cache DNS lookups locally may
3311 help, and is a good idea for speeding up other services as well.
3312 Switching to a faster MTA like <a
3313 href="http://www.postfix.org/">Postfix</a> might help.</p>
3315 <h2><a id="O7" name="O7">O7. Why doesn't fetchmail deliver mail in
3316 date-sorted order?</a></h2>
3318 <p>Because that's not the order the server hands it to fetchmail
3321 <p>Fetchmail getting mail from a POP server delivers mail in the
3322 order that your server delivers mail. Fetchmail can't do anything
3323 about this; it's a limitation of the underlying POP protocol.</p>
3325 <p>In theory it might be possible for fetchmail in IMAP mode to
3326 sort messages by date, but this would be in violation of two basics
3327 of fetchmail's design philosophy: (a) to be as simple and
3328 transparent a pipe as possible, and (b) to <em>hide</em>, rather
3329 than emphasize, the differences between the remote-fetch protocols
3332 <p>Re-ordering messages is a user-agent function, anyway.</p>
3334 <h2><a id="O8" name="O8">O8. I'm using pppd. Why isn't my monitor
3335 option working?</a></h2>
3337 <p>There is a combination of circumstances that can confuse
3338 fetchmail. If you have set up demand dialing with pppd, and pppd
3339 has an idle timeout, and you have lcp-echo-interval set, then the
3340 lcp-echo-interval time must be longer than the pppd idle timeout.
3341 Otherwise it is going keep increasing the packet counters that
3342 fetchmail relies upon, triggering fetchmail into polling after its
3343 own delay interval and thus preventing the pppd link from ever
3344 reaching its inactivity timeout.</p>
3346 <h2><a id="O9" name="O9">O9. Why does fetchmail keep retrieving the
3347 same messages over and over?</a></h2>
3349 <p>First, check to see that you haven't enabled the
3350 <cite>keep</cite> and <cite>fetchall</cite> option. If you have,
3351 turn one of them off - which one, depends on why they have been set in
3352 the first place, and to a lesser degree on the upstream server.</p>
3354 <p>This can also happen when some other mail client is logged in to
3355 your mail server, if it uses a simple exclusive-locking scheme (and
3356 many, especially most POP3 servers, do exactly that). Your
3357 fetchmail is able to retrieve the messages, but because the mailbox
3358 is write-locked by the other instance yours can neither mark
3359 messages seen or delete them. The solution is to either (a) wait
3360 for the other client to finish, or (b) terminate it.</p>
3362 <h2><a id="O10" name="O10"><strike>O10. Why is the received date on all my
3363 messages the same?i</strike></a></h2>
3365 <p>The answer that used to be here made no sense.</p>
3367 <h2><a name="O11">O11. I keep getting messages that say "Repoll
3368 immediately" in my logs.</a></h2>
3370 <p>This is your server barfing on the CAPA probe that fetchmail sends.
3371 Because some servers like to drop the connection after that probe,
3372 fetchmail will re-poll immediately with this probe defeated.</p>
3374 <p>If you run fetchmail in daemon mode (say "set daemon 600"), you will
3375 get the message only once per run.</p>
3377 <p>If you set an authentication method explicitly (say, with
3378 <code>auth password</code>), you will never get the message.</p>
3380 <h2><a name="O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a></h2>
3382 <p>This is a feature, not a bug.</p>
3384 <p>Any 4xx response (like 451) indicates a transient (temporary) error.
3385 This means that the mail could be accepted if retried later. Lookup
3386 failures are normally transient errors as a mail should not get
3387 rejected if a dns server is unreachable or down.</p>
3389 <p>A permanent reject response is of the form 5xx (like 550).</p>
3391 <p>You could tell your SMTP server to not lookup any addresses if you are
3392 not keen on checking the sender addresses. This problem typically
3393 occurs if your mail server is not checking the sender addresses, but
3394 your local server is.</p>
3396 <p>Or you could declare <code>antispam 451</code>, which is not
3397 recommended though, as it may cause mail loss.</p>
3399 <p>Or, you could check your nameserver configuration and query logs for
3402 <p>All these issues are not related to fetchmail directly.</p>
3404 <h2><a name="O13">O13. I want timestamp information in my fetchmail logs.</a></h2>
3406 <p>Write a <code>preconnect</code> command in your configuration file that
3407 does something like "date >> $HOME/fetchmail.log".</p>
3409 <h2><a name="O14">O14. Fetchmail no longer deletes oversized mails with
3412 <p>Use <code>--limitflush</code> (available since release 6.3.0) to
3413 delete oversized mails along with the <code>--limit</code> option. If
3414 you are already having <code>flush</code> in your rcfile to delete
3415 oversized mails, <em>replace</em> it with <code>limitflush</code> to
3416 avoid losing mails unintentionally.</p>
3418 <p>The <code>--flush</code> option is primarily designed to delete
3419 mails which have been read/downloaded but not deleted yet. This option
3420 cannot be overloaded to delete oversized mails as it cannot be guessed
3421 whether the user wants to delete only read/downloaded mails or only
3422 oversized mails or both when a user specifies both
3423 <code>--limit</code> and <code>--flush</code>. Hence, a separate
3424 <code>--limitflush</code> has been added to resolve the ambiguity.</p>
3426 <h2><a name="O15">O15. Fetchmail always retains the first message in the
3429 <p>This happens when fetchmail sees an "X-IMAP:" header in the very
3430 first message in your mailbox. This usually stems from a message like
3431 the one shown below, which is automatically created on your server. This
3432 message shows up if the University of Washington IMAP or PINE software
3433 is used on the server together with a POP2 or POP3 daemon that is not
3434 aware of these messages, such as some versions of Qualcomm Popper
3439 From MAILER-DAEMON Wed Nov 23 11:38:42 2005
3440 Date: 23 Nov 2005 11:38:42 +0100
3441 From: Mail System Internal Data <MAILER-DAEMON@imap.example.org>
3442 Subject: DON'T DELETE THIS MESSAGE -- FOLDER INTERNAL DATA
3443 Message-ID: <1132742322@imap.example.org>
3444 X-IMAP: 1132742306 0000000001
3447 This text is part of the internal format of your mail folder, and is not
3448 a real message. It is created automatically by the mail system software.
3449 If deleted, important folder data will be lost, and it will be re-created
3450 with the data reset to initial values.
3454 <p>As this message does not contain useful information, fetchmail is not
3455 retrieving it. And deleting it might slow down the server if you are
3456 keeping messages on the server, and the server would recreate it
3457 anyways, that's why fetchmail does not bother to delete it either.</p>
3459 <h2><a name="O16">O16. Why is the Fetchmail FAQ only available in
3460 ISO-216 A4 format? How do I get the FAQ in Letter format?</a></h2>
3462 <p>All the world uses ISO-216:1975 "A4" paper except for North America.
3463 Using A4 format reaches far more people than (formerly known as DIN A4,
3464 from DIN 476) format. Besides that, A4 paper <em>is</em> available in North
3466 For further information on the Letter-vs-A4 story, see:</p>
3467 <ul><li><a href="http://www.cl.cam.ac.uk/~mgk25/iso-paper.html">Markus
3468 Kuhn: "International standard paper sizes"</a></li>
3470 href="http://betweenborders.com/wordsmithing/a4-vs-us-letter/">Brian
3471 Forte: "A4 vs US Letter"</a></li></ul>
3473 <p>Offering the document formatted for two different paper sizes would
3474 bloat the package beyond reason, and formatting in a way that fits A4
3475 and Letter paper formats would be a waste of paper in most parts of the
3476 world. For that reason, fetchmail only ships with an A4 formatted PDF
3479 <p>To create a letter-sized PDF, install <a
3480 href="http://www.htmldoc.org/">HTMLDOC</a>, edit
3481 <code>fetchmail-FAQ.book</code> in the source directory with your
3482 favorite text editor, replace <samp>--size A4</samp> by <samp>--size
3483 letter</samp>, and type:
3486 make fetchmail-FAQ.pdf
3491 <table width="100%" cellpadding="0" summary="Canned page footer">
3493 <td width="30%">Back to <a href="index.html">Fetchmail Home
3495 <td width="30%" align="right">$Date$</td>
3500 <address>Eric S. Raymond <a
3501 href="mailto:esr@thyrsus.com"><esr@thyrsus.com></a><br />
3502 Matthias Andree</address>