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14 <td width="30%">Back to <a href="index.html">Fetchmail Home
16 <td width="30%" align="right">$Date$</td>
21 <h1>Frequently Asked Questions About Fetchmail</h1>
23 <p>Before reporting any bug, please read <a href="#G3">G3</a> for
24 advice on how to include diagnostic information that will get your
25 bug fixed as quickly as possible.</p>
27 <p>If you have a question or answer you think ought to be added to
28 this FAQ list, file it to one of the trackers at <a
29 href="http://developer.berlios.de/projects/fetchmail/">our BerliOS
30 project site</a> or post to one of the fetchmail mailing lists (see
33 <h1>General questions:</h1>
35 <a href="#G1">G1. What is fetchmail and why should I bother?</a><br/>
36 <a href="#G2">G2. Where do I find the latest FAQ and fetchmail sources?</a><br/>
37 <a href="#G3">G3. I think I've found a bug. Will you fix it?</a><br/>
38 <a href="#G4">G4. I have this idea for a neat feature. Will you add it?</a><br/>
39 <a href="#G5">G5. I want to make fetchmail behave like Outlook Express.</a><br/>
40 <a href="#G6">G6. Is there a mailing list for exchanging tips?</a><br/>
41 <a href="#G7">G7. So, what's this I hear about a fetchmail paper?</a><br/>
42 <a href="#G8">G8. What is the best server to use with fetchmail?</a><br/>
43 <a href="#G9">G9. What is the best mail program to use with fetchmail?</a><br/>
44 <a href="#G10">G10. How can I avoid sending my password en clair?</a><br/>
45 <a href="#G11">G11. Is any special configuration needed to use a dynamic IP address?</a><br/>
46 <a href="#G12">G12. Is any special configuration needed to use firewalls?</a><br/>
47 <a href="#G13">G13. Is any special configuration needed to <em>send</em> mail?</a><br/>
48 <a href="#G14">G14. Is fetchmail Y2K-compliant?</a><br/>
49 <a href="#G15">G15. Is there a way in fetchmail to support disconnected IMAP mode?</a><br/>
50 <a href="#G16">G16. How will fetchmail perform under heavy loads?</a><br/>
53 <h1>Build-time problems:</h1>
55 <a href="#B1">B1. Make coughs and dies when building on FreeBSD.</a><br/>
56 <a href="#B2">B2. Lex bombs out while building the fetchmail lexer.</a><br/>
57 <a href="#B3">B3. I get link failures when I try to build fetchmail.</a><br/>
58 <a href="#B4">B4. I get build failures in the intl directory.</a><br/>
60 <h1>Fetchmail configuration file grammar questions:</h1>
62 <a href="#F1">F1. Why does my old .fetchmailrc no longer work?</a><br/>
63 <a href="#F2">F2. The .fetchmailrc parser won't accept my all-numeric user name.</a><br/>
64 <a href="#F3">F3. The .fetchmailrc parser won't accept my host or username beginning with 'no'.</a><br/>
65 <a href="#F4">F4. I'm getting a 'parse error' message I don't understand.</a><br/>
67 <h1>Configuration questions:</h1>
69 <a href="#C1">C1. Why do I need a .fetchmailrc when running as root
70 on my own machine?</a><br/>
71 <a href="#C2">C2. How can I arrange for a fetchmail daemon to get
72 killed when I log out?</a><br/>
73 <a href="#C3">C3. How do I know what interface and address to use
74 with --interface?</a><br/>
75 <a href="#C4">C4. How can I set up support for sendmail's anti-spam
77 <a href="#C5">C5. How can I poll some of my mailboxes more/less
78 often than others?</a><br/>
79 <a href="#C6">C6. Fetchmail works OK started up manually, but not
80 from an init script.</a><br/>
81 <a href="#C7">C7. How can I forward mail to another
85 <h1>How to make fetchmail play nice with various MTAs:</h1>
87 <a href="#T1">T1. How can I use fetchmail with sendmail?</a><br/>
88 <a href="#T2">T2. How can I use fetchmail with qmail?</a><br/>
89 <a href="#T3">T3. How can I use fetchmail with exim?</a><br/>
90 <a href="#T4">T4. How can I use fetchmail with smail?</a><br/>
91 <a href="#T5">T5. How can I use fetchmail with SCO's MMDF?</a><br/>
92 <a href="#T6">T6. How can I use fetchmail with Lotus Notes?</a><br/>
93 <a href="#T7">T7. How can I use fetchmail with Courier IMAP?</a><br/>
94 <a href="#T8">T8. How can I use fetchmail with vbmailshield?</a><br/>
96 <h1>How to make fetchmail work with various servers:</h1>
98 <a href="#S1">S1. How can I use fetchmail with qpopper?</a><br/>
99 <a href="#S2">S2. How can I use fetchmail with Microsoft Exchange?</a><br/>
100 <a href="#S3">S3. How can I use fetchmail with HP OpenMail?</a><br/>
101 <a href="#S4">S4. How can I use fetchmail with Novell GroupWise?</a><br/>
102 <a href="#S5">S5. How can I use fetchmail with InterChange?</a><br/>
103 <a href="#S6">S6. How can I use fetchmail with MailMax?</a><br/>
104 <a href="#S7">S7. How can I use fetchmail with FTGate?</a><br/>
106 <h1>How to fetchmail work with specific ISPs:</h1>
108 <a href="#I1">I1. How can I use fetchmail with Compuserve RPA?</a><br/>
109 <a href="#I2">I2. How can I use fetchmail with Demon Internet's SDPS?</a><br/>
110 <a href="#I3">I3. How can I use fetchmail with usa.net's servers?</a><br/>
111 <a href="#I4">I4. How can I use fetchmail with geocities POP3 servers?</a><br/>
112 <a href="#I5">I5. How can I use fetchmail with Hotmail or Lycos Webmail?</a><br/>
113 <a href="#I6">I6. How can I use fetchmail with MSN?</a><br/>
114 <a href="#I7">I7. How can I use fetchmail with SpryNet?</a><br/>
115 <a href="#I8">I8. How can I use fetchmail with comcast.net?</a><br/>
117 <h1>How to set up well-known security and authentication
120 <a href="#K1">K1. How can I use fetchmail with SOCKS?</a><br/>
121 <a href="#K2">K2. How can I use fetchmail with IPv6 and IPsec?</a><br/>
122 <a href="#K3">K3. How can I get fetchmail to work with ssh?</a><br/>
123 <a href="#K4">K4. What do I have to do to use the IMAP-GSS protocol?</a><br/>
124 <a href="#K5">K5. How can I use fetchmail with SSL?</a><br/>
125 <a href="#K6">K6. How can I tell fetchmail not to try TLS if the server
126 advertises it?</a><br/>
128 <h1>Runtime fatal errors:</h1>
130 <a href="#R1">R1. Fetchmail isn't working, and -v shows 'SMTP
131 connect failed' messages.</a><br/>
132 <a href="#R2">R2. When I try to configure an MDA, fetchmail doesn't
134 <a href="#R3">R3. Fetchmail dumps core when given an invalid rc
136 <a href="#R4">R4. Fetchmail dumps core in -V mode, but operates
137 normally otherwise.</a><br/>
138 <a href="#R5">R5. Running fetchmail in daemon mode doesn't
140 <a href="#R6">R6. Fetchmail randomly dies with socket errors.</a><br/>
141 <a href="#R7">R7. Fetchmail running as root stopped working after
142 an OS upgrade</a><br/>
143 <a href="#R8">R8. Fetchmail is timing out after fetching certain
144 messages but before deleting them</a><br/>
145 <a href="#R9">R9. Fetchmail is timing out during message fetches</a><br/>
146 <a href="#R10">R10. Fetchmail is dying with SIGPIPE.</a><br/>
147 <a href="#R11">R11. My server is hanging or emitting errors on CAPA.</a><br/>
148 <a href="#R12">R12. Fetchmail isn't working and reports getaddrinfo
150 <h1>Hangs and lockups:</h1>
152 <a href="#H1">H1. Fetchmail hangs when used with pppd.</a><br/>
153 <a href="#H2">H2. Fetchmail hangs during the MAIL FROM
155 <a href="#H3">H3. Fetchmail hangs while fetching mail.</a><br/>
158 <h1>Disappearing mail:</h1>
160 <a href="#D1">D1. I think I've set up fetchmail correctly, but I'm
161 not getting any mail.</a><br/>
162 <a href="#D2">D2. All my mail seems to disappear after a dropped
164 <a href="#D3">D3. Mail that was being fetched when I interrupted my
165 fetchmail seems to have been vanished.</a><br/>
168 <h1>Multidrop-mode problems:</h1>
170 <a href="#M1">M1. I've declared local names, but all my multidrop
171 mail is going to root anyway.</a><br/>
172 <a href="#M2">M2. I can't seem to get fetchmail to route to a local
173 domain properly.</a><br/>
174 <a href="#M3">M3. I tried to run a mailing list using multidrop,
175 and I have a mail loop!</a><br/>
176 <a href="#M4">M4. My multidrop fetchmail seems to be having DNS
178 <a href="#M5">M5. I'm seeing long DNS delays before each message is
180 <a href="#M6">M6. How do I get multidrop mode to work with
182 <a href="#M7">M7. Multidrop mode isn't parsing envelope addresses
183 from my Received headers as it should.</a><br/>
184 <a href="#M8">M8. Users are getting multiple copies of
188 <h1>Mangled mail:</h1>
190 <a href="#X1">X1. Spurious blank lines are appearing in the headers
191 of fetched mail.</a><br/>
192 <a href="#X2">X2. My mail client can't see a Subject
194 <a href="#X3">X3. Messages containing "From" at start of line are
195 being split.</a><br/>
196 <a href="#X4">X4. My mail is being mangled in a new and different
198 <a href="#X5">X5. Using POP3, retrievals seems to be fetching too
200 <a href="#X6">X6. My mail attachments are being dropped or
202 <a href="#X7">X7. Some mail attachments are hanging
204 <a href="#X8">X8. A spurious ) is being appended to my
207 <h1>Other problems:</h1>
209 <a href="#O1">O1. The --logfile option doesn't work if the logfile
210 doesn't exist.</a><br/>
211 <a href="#O2">O2. Every time I get a POP or IMAP message the header
212 is dumped to all my terminal sessions.</a><br/>
213 <a href="#O3">O3. Does fetchmail reread its rc file every poll
215 <a href="#O4">O4. Why do deleted messages show up again when I take
216 a line hit while downloading?</a><br/>
217 <a href="#O5">O5. Why is fetched mail being logged with my name,
218 not the real From address?</a><br/>
219 <a href="#O6">O6. I'm seeing long sendmail delays or hangs near the
220 start of each poll cycle.</a><br/>
221 <a href="#O7">O7. Why doesn't fetchmail deliver mail in date-sorted
223 <a href="#O8">O8. I'm using pppd. Why isn't my monitor option
225 <a href="#O9">O9. Why does fetchmail keep retrieving the same
226 messages over and over?</a><br/>
227 <a href="#O10">O10. Why is the received date on all my messages the
229 <a href="#O11">O11. I keep getting messages that say "Repoll
230 immediately" in my logs.</a><br/>
231 <a href="#O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a><br/>
232 <a href="#O13">O13. I want timestamp information in my fetchmail logs.</a>
237 <h2><a id="G1" name="G1">G1. What is fetchmail and why should I
240 <p>Fetchmail is a one-stop solution to the remote mail retrieval
241 problem for Unix machines, quite useful to anyone with an
242 intermittent PPP or SLIP connection to a remote mailserver. It can
243 collect mail using any variant of POP or IMAP and forwards via port
244 25 to the local SMTP listener, enabling all the normal
245 forwarding/filtering/aliasing mechanisms that would apply to local
246 mail or mail arriving via a full-time TCP/IP connection.</p>
248 <p>Fetchmail is not a toy or a coder's learning exercise, but an
249 industrial-strength tool capable of transparently handling every
250 retrieval demand from those of a simple single-user ISP connection
251 up to mail retrieval and rerouting for an entire client domain.
252 Fetchmail is easy to configure, unobtrusive in operation, powerful,
253 feature-rich, and well documented.</p>
255 <p>Fetchmail is <a href="http://www.opensource.org">open-source</a>
256 software. The openness of the sources is the strongest assurance of
257 quality you can have. Extensive peer review by a large,
258 multi-platform user community has shown that fetchmail is as near
259 bulletproof as the underlying protocols permit.</p>
261 <p>Fetchmail is licensed under the <a
262 href="http://gnu.org//copyleft/gpl.html">GNU General Public
265 <p>If you found this FAQ in the distribution, see the README for
266 fetchmail's full feature list.</p>
269 <h2><a id="G2" name="G2">G2. Where do I find the latest FAQ and
270 fetchmail sources?</a></h2>
272 <p>The latest HTML FAQ is available alongside the latest fetchmail
273 sources at the fetchmail home page: <a
274 href="http://fetchmail.berlios.de/">http://fetchmail.berlios.de/</a>.
275 You can also usually find both in the <a
276 href="http://sunsite.unc.edu/pub/Linux/system/mail/pop/!INDEX.html">
277 POP mail tools directory on Sunsite</a>.</p>
279 <p>A text dump of this FAQ is included in the fetchmail
280 distribution. Because it freezes at distribution release time, it
281 may not be completely current.</p>
284 <h2><a id="G3" name="G3">G3. I think I've found a bug. Will you fix
287 <p>Yes I will, provided you include enough diagnostic information
288 for me to go on. Send bugs to <a
289 href="mailto:fetchmail-users@lists.berlios.de">fetchmail-users</a>.
290 When reporting bugs, please include the following:</p>
293 <li>Your operating system.</li>
295 <li>Your compiler version, if you built from source; otherwise, the
296 name and origin of the RPM or other binary package you
299 <li>A copy of your POP or IMAP server's greeting line.</li>
301 <li>The name and version of the SMTP listener or MDA you are
304 <li>Any command-line options you used.</li>
306 <li>The output of fetchmail -V called with whatever other
307 command-line options you used.</li>
310 <p>If you have FTP access to your remote mail account, and you have
311 any suspicion that the bug was triggered by a particular message,
312 please include a copy of the message that triggered the bug.</p>
314 <p>Often, the first thing I will do when you report a bug is tell
315 you to upgrade to the newest version of fetchmail, and then see if
316 the problem reproduces. So you'll probably save us both time if you
317 upgrade and test with the latest version <em>before</em> sending in
320 <p>If your bug is something that used to work but stopped working
321 when you upgraded, then you can help pin the bug down by trying <a
322 href="http://download.berlios.de/fetchmail/">intermediate versions
323 of fetchmail</a> until you identify the revision that broke your
324 feature. The smart way to do this is by binary search on the
325 version sequence. First, try the version halfway between your last
326 good one and the current one. If it works, the failure was
327 introduced in the upper half of the sequence; if it doesn't, the
328 failure was introduced in the lower half. Now bisect that half in
329 the same way. In a very few tries, you should be able to identify
330 the exact adjacent pair of versions between which your bug was
331 introduced -- and with information like that, I can usually come up
332 with a fix very quickly.</p>
334 <p>Another useful thing you can do, if you're using POP3, is to
335 test for IMAP4 support on your mailserver using the autoprobe
336 function of fetchmailconf. If you have IMAP4, and fetchmailconf
337 doesn't tell you it's broken, switch immediately. POP3 is a weak,
338 poorly-designed protocol with chronic problems, and the later
339 versions after RFC1725 actually get worse rather than better.
340 Changing over to IMAP4 may well make your problem go away -- and if
341 your ISP doesn't have IMAP4 support, bug them to supply it.</p>
343 <p>It is helpful if you include your .fetchmailrc file, but not
344 necessary unless your symptom seems to involve an error in
345 configuration parsing. If you do send in your .fetchmailrc, mask
346 the passwords first!</p>
348 <p>If fetchmail seems to run and fetch mail, but the headers look
349 mangled (that is, headers are missing or blank lines are inserted
350 in the headers) then read the FAQ items in section <a
351 href="#X1">X</a> before submitting a bug report. Pay special
352 attention to the item on <a href="#generic_mangling">diagnosing
353 mail mangling</a>. There are lots of ways for other programs in the
354 mail chain to screw up that look like fetchmail's fault, but you
355 may be able to fix these by tweaking your configuration.</p>
357 <p>A transcript of the failed session with -v -v (yes, that's
358 <em>two</em> -v options, enabling debug mode) will almost always be
359 useful. It is very important that the transcript include your
360 POP/IMAP server's greeting line, so I can identify it in case of
361 server problems. This transcript will not reveal your passwords,
362 which are specially masked out precisely so transcripts can be
365 <p>If you upgraded your fetchmail and something broke, you should
366 include session transcripts with -v -v of both the working and
367 failing versions. Very often, the source of the problem can
368 instantly identified by looking at the differences in protocol
371 <p>If the bug involves a core dump or hang, a gdb stack trace is
372 good to have. (Bear in mind that you can attach gdb to a running
373 but hung process by giving the process ID as a second argument.)
374 You will need to reconfigure with:</p>
377 CFLAGS=-g LDFLAGS=" " ./configure
380 <p>Then rebuild in order to generate a version that can be
383 <p>Best of all is a mail file which, when fetched, will reproduce
384 the bug under the latest (current) version.</p>
386 <p>Any bug I can reproduce will usually get fixed very quickly,
387 often within 48 hours. Bugs I can't reproduce are a crapshoot. If
388 the solution isn't obvious when I first look, it may evade me for a
389 long time (or to put it another way, fetchmail is well enough
390 tested that the easy bugs have long since been found). So if you
391 want your bug fixed rapidly, it is not just sufficient but nearly
392 <em>necessary</em> that you give me a way to reproduce it.</p>
395 <h2><a id="G4" name="G4">G4. I have this idea for a neat feature.
396 Will you add it?</a></h2>
398 <p>Probably not. Most of the feature suggestions I get are for ways
399 to set various kinds of administrative policy or add more spam
400 filtering (the most common one, which I used to get about four
401 million times a week and got <em>really</em> tired of, is for
402 tin-like kill files).</p>
404 <p>You can do spam filtering better with procmail or maildrop on
405 the server side and (if you're the server sysadmin) sendmail.cf
406 domain exclusions. If you really want fetchmail to do it from the
407 client side, use a <code>preconnect</code> command to call
408 <a href='http://mailfilter.sourceforge.net/'>mailfilter</a>.</p>
410 <p>You can do other policy things better with the
411 <code>mda</code> option and script wrappers around fetchmail. If
412 it's a prime-time-vs.-non-prime-time issue, ask yourself whether a
413 wrapper script called from crontab would do the job.</p>
415 <p>I'm not going to do these; fetchmail's job is transport, not
416 policy, and I refuse to change it from doing one thing well to
417 attempting many things badly. One of my objectives is to keep
418 fetchmail simple so it stays reliable.</p>
420 <p>For reasons fetchmail doesn't have other commonly-requested
421 features (such as password encryption, or multiple concurrent polls
422 from the same instance of fetchmail) see <a
423 href="esrs-design-notes.html">ESR's design
424 notes</a>. Note that this document is partially obsoleted by the
425 <a href="design-notes.html">updated design notes.</a></p>
427 <p>Fetchmail is a mature project, no longer in constant active
428 development. It is no longer my top project, and I am going to be
429 quite reluctant to add features that might either jeopardize its
430 stability or involve me in large amounts of coding.</p>
432 <p>All that said, if you have a feature idea that really is about a
433 transport problem that can't be handled anywhere but fetchmail, lay
434 it on me. I'm very accommodating about good ideas.</p>
437 <h2><a id="G5" name="G5">G5. I want to make fetchmail behave like
438 Outlook Express.</a></h2>
440 <p>The second-most-requested feature for fetchmail, after
441 content-based filtering, is the ability to have it remove messages
442 from a maildrop after N days, typically to be used with the
443 <code>keep</code> option as a sort of poor man's newsgroup
444 facility. Microsoft's Outlook Express supports this.</p>
446 <p>This feature won't be added either. Repeat after me: fetchmail's
447 job is transport, not policy. If you want this, write a Perl or
448 Python script, to be run from a cron job, that deletes old messages
449 off your maildrop. Send it to me and I'll put it in the contrib
453 <h2><a id="G6" name="G6">G6. Is there a mailing list for exchanging
456 <p>There is a fetchmail-users list (fetchmail-users@lists.berlios.de)
457 for bug reports and people who want to discuss configuration issues of
458 fetchmail. It's a Mailman list, see <a
459 href="http://lists.berlios.de/mailman/listinfo/fetchmail-users">http://lists.berlios.de/mailman/listinfo/fetchmail-users</a>.</p>
460 <p>There is a fetchmail-devel list
461 (fetchmail-devel@lists.berlios.de) for people who want to discuss
462 fixes and improvements in fetchmail and help co-develop it. It's a
463 Mailman list, which you can sign up for at <a
464 href="http://lists.berlios.de/mailman/listinfo/fetchmail-devel">http://lists.berlios.de/mailman/listinfo/fetchmail-devel</a>.
465 There is also an announcements-only list,
466 fetchmail-announce@lists.berlios.de, which you can sign up for at <a
467 href="http://lists.berlios.de/mailman/listinfo/fetchmail-announce">http://lists.berlios.de/mailman/listinfo/fetchmail-announce</a>.</p>
470 <h2><a id="G7" name="G7">G7. So, what's this I hear about a
471 fetchmail paper?</a></h2>
473 <p>The fetchmail development was also a sociological experiment, an
474 extended test to see if my theory about the critical features of
475 the Linux development model is correct.</p>
477 <p>The experiment was a success. I wrote a paper about it titled <a
478 href="http://www.catb.org/~esr/writings/cathedral.html">The
479 Cathedral and the Bazaar</a> which was first presented at Linux
480 Kongress '97 in Bavaria and very well received there. It was also
481 given at Atlanta Linux Expo, Linux Pro '97 in Warsaw, and the first
482 Perl Conference, at UniForum '98, and was the basis of an invited
483 presentation at Usenix '98. The folks at Netscape tell me it helped
485 href="http://www.netscape.com/newsref/pr/newsrelease558.html">give
486 away the source for Netscape Communicator</a>.</p>
488 <p>If you're reading a non-HTML dump of this FAQ, you can find the
489 paper on the Web with a search for that title.</p>
492 <h2><a id="G8" name="G8">G8. What is the best server to use with
495 <p>The short answer: IMAP 2000 running over Unix.</p>
497 <p>Here's a longer answer:</p>
499 <p>Fetchmail will work with any POP, IMAP, ETRN, or ODMR server
500 that conforms to the relevant RFCs (and even some outright broken
501 ones like <a href="#S2">Microsoft Exchange</a> and <a
502 href="#S6">Novell GroupWise</a>). This doesn't mean it works
503 equally well with all, however. POP2 servers, and POP3 servers
504 without LAST, limit fetchmail's capabilities in various ways
505 described on the manual page.</p>
507 <p>Most modern Unixes (and effectively all Linux/*BSD systems) come
508 with POP3 support preconfigured (but beware of the horribly broken
509 POP3 server mentioned in <a href="#D2">D2</a>). An increasing
510 minority also feature IMAP (you can detect IMAP support by running
511 fetchmail in AUTO mode, or by using the 'Probe for supported
512 protocols' function in the fetchmailconf utility).</p>
514 <p>If you have the option, we recommend using or installing an
515 IMAP4rev1 server; it has the best facilities for tracking message
516 'seen' states. It also recovers from interrupted connections more
517 gracefully than POP3, and enables some significant performance
518 optimizations. The new <a
519 href="ftp://ftp.cac.washington.edu/imap/imap.tar.Z">IMAP 2000</a>
520 is particularly nice, as it supports CRAM-MD5 so you don't have to
521 ship your mail password over the net en clair (fetchmail
522 autodetects this capability). Older versions had support for GSSAPI
523 giving a similar effect.</p>
525 <p>Don't be fooled by NT/Exchange propaganda. M$ Exchange is just
526 plain broken (see item <a href="#S2">S2</a>) and NT cannot handle
527 the sustained load of a high-volume remote mail server. Even
528 Microsoft itself knows better than to try this; their own Hotmail
529 service runs over Solaris! For extended discussion, see John
530 Kirch's excellent <a href="http://unix-vs-nt.org/kirch/">white
531 paper</a> on Unix vs. NT performance.</p>
533 <p>Source for a high-quality supported implementation of POP is
534 available from the <a
535 href="ftp://ftp.qualcomm.com/eudora/servers/unix/popper/">Eudora
536 FTP site</a>. Don't use 2.5, which has a rather restrictive
537 license. The 2.5.2 version appears to restore the open-source
538 license of previous versions.</p>
541 <h2><a id="G9" name="G9">G9. What is the best mail program to use
542 with fetchmail?</a></h2>
544 <p>Fetchmail will work with all popular <a href="#T1">mail
545 transport programs</a>. It also doesn't care which user agent you
546 use, and user agents are as a rule almost equally indifferent to
547 how mail is delivered into your system mailbox. So any of the
548 popular Unix mail agents -- <a
549 href="http://www.myxa.com/old/elm.html">elm</a>, <a
550 href="http://www.washington.edu/pine/">pine</a>, <a
551 href="http://www.cs.indiana.edu/docproject/mail/mh.html">mh</a>, or
552 <a href="http://www.mutt.org">mutt</a> -- will work fine with
555 <p>All this having been said, I can't resist putting in a discreet
556 plug for <a href="http://www.mutt.org">mutt</a>. My own personal
557 mail setup is sendmail plus fetchmail plus mutt. Mutt's interface
558 is only a little different from that of its now-moribund ancestor
559 elm, but its excellent handling of MIME and PGP put it in a class
560 by itself. You won't need its built-in POP3 support, though; most
561 of the mutt developers will cheerfully admit that fetchmail's is
565 <h2><a id="G10" name="G10">G10. How can I avoid sending my password
568 <p>Depending on what your mail server you are talking to, this
569 ranges from trivial to impossible. It may even be next to
572 <p>Most people use fetchmail over phone wires (whether plain old
573 copper or DSL), which are hard to tap. Anybody with the skill and
574 resources to do this could get into your server mailbox with much less
575 effort by subverting the server host. So if your provider setup is
576 phone-company wire going straight into a service box, you probably
577 don't need to worry.</p>
579 <p>In general there is little point in trying to secure your fetchmail
580 transaction unless you trust the security of the server host you are
581 retrieving mail from. Your vulnerability is more likely to be an
582 insecure local network on the server end (e.g. to somebody with a
583 TCP/IP packet sniffer intercepting Ethernet traffic between the modem
584 concentrator or DSL POP you dial in to and the mailserver host).</p>
586 <p>Having realized this, you need to ask whether password
587 encryption alone will really address your security exposure. If you
588 think you might be snooped between server and client, it's better
589 to use end-to-end encryption on your whole mail stream so none of
590 it can be read. One of the advantages of fetchmail over
591 conventional SMTP-push delivery is that you may be able to arrange
592 this by using ssh(1); see <a href="#K3">K3</a>.</p>
594 <p>Note that ssh is not a complete privacy solution either, as your
595 mail could have been snooped in transit to your POP server from
596 wherever it originated. For best security, agree with your
597 correspondents to use a tool such as <a
598 href="http://www.gnupg.org/">GPG</a> (Gnu Privacy Guard) or PGP
599 (Pretty Good Privacy).</p>
601 <p>If ssh/sshd isn't available, or you find it too complicated for
602 you to set up, password encryption will at least keep a malicious
603 cracker from deleting your mail, and require him to either tap your
604 connection continuously or crack root on the server in order to
607 <p>You can deduce what encryptions your mail server has available
608 by looking at the server greeting line (and, for IMAP, the response
609 to a CAPABILITY query). Do a <code>fetchmail -v</code> to see
610 these, or telnet direct to the server port (110 for POP3, 143 for
613 <p>If your mailserver is using IMAP 2000, you'll have CRAM-MD5
614 support built in. Fetchmail autodetects this; you can skip the rest
617 <p>The POP3 facility you are most likely to have available is APOP.
618 This is a POP3 feature supported by many servers (fetchmailconf's
619 autoprobe facility will detect it and tell you if you have it). If
620 you see something in the greeting line that looks like an
621 angle-bracket-enclosed Internet address with a numeric left-hand
622 part, that's an APOP challenge (it will vary each time you log in).
623 You can register a secret on the host (using
624 <code>popauth(8)</code> or some program like it). Specify the
625 secret as your password in your .fetchmailrc; it will be used to
626 encrypt the current challenge, and the encrypted form will be sent
627 back the the server for verification.</p>
629 <p>Alternatively, you may have Kerberos available. This may require
630 you to set up some magic files in your home directory on your
631 client machine, but means you can omit specifying any password at
634 <p>Fetchmail supports two different Kerberos schemes. One is a POP3
635 variant called KPOP; consult the documentation of your mail server
636 to see if you have it (one clue is the string "krb-IV" in the
637 greeting line on port 110). The other is an IMAP and POP3 facility
638 described by RFC1731 and RFC1734. You can tell if this one is
639 present by looking for AUTH=KERBEROS_V4 in the CAPABILITY
642 <p>If you are fetching mail from a CompuServe POP3 account, you can
643 use their RPA authentication (which works much like APOP). See <a
644 href="#I1">I1</a> for details. If you are fetching mail from
645 Microsoft Exchange using IMAP, you will be able to use NTLM.</p>
647 <p>Your POP3 server may have the RFC1938 OTP capability to use
648 one-time passwords (if it doesn't, you can get OTP patches for the
649 2.2 version of the Qualcomm popper from <a href="#cmetz">Craig
650 Metz</a>). To check this, look for the string "otp-" in the
651 greeting line. If you see it, and your fetchmail was built with
652 OPIE support compiled in (see the distribution INSTALL file),
653 fetchmail will detect it also. When using OTP, you will specify a
654 password but it will not be sent en clair.</p>
656 <p>You can get both POP3 and IMAP OTP patches from <a id="cmetz"
657 name="cmetz">Craig Metz</a> at <a
658 href="http://www.inner.net/opie">http://www.inner.net/opie</a>.</p>
660 <p>These patches use a SASL authentication method named "X-OTP"
661 because there is not currently a standard way to do this; fetchmail
662 also uses this method, so the two will interoperate happily. They
663 better, because this is how Craig gets his mail ;-)</p>
665 <p>Finally, you can use <a href="#K5">SSL</a> for complete
666 end-to-end encryption if you have an SSL-enabled mailserver.</p>
669 <h2><a id="G11" name="G11">G11. Is any special configuration needed
670 to use a dynamic IP address?</a></h2>
672 <p>Yes. In order to avoid giving indigestion to certain picky MTAs
673 (notably <a href="#T3">exim</a>), fetchmail always makes the RCPT
674 TO address it feeds the MTA a fully qualified one with a hostname
675 part. Normally it does this by appending @ and "localhost", but
676 when you are using Kerberos or ETRN mode it will append @ and your
677 machine's fully-qualified domain name (FQDN).</p>
679 <p>Appending the FQDN can create problems when fetchmail is running
680 in daemon mode and outlasts the dynamic IP address assignment your
681 client machine had when it started up.</p>
683 <p>Since the new IP address (looked up at RCPT TO interpretation
684 time) doesn't match the original, the most benign possible result
685 is that your MTA thinks it's seeing a relaying attempt and refuses.
686 More frequently, fetchmail will try to connect to a nonexistent
687 host address and time out. Worst case, you could up forwarding your
688 mail to the wrong machine!</p>
690 <p>Use the <code>smtpaddress</code> option to force the appended
691 hostname to one with a (fixed) IP address of 127.0.0.1 in your
692 <code>/etc/hosts</code>. (The name 'localhost' will usually work;
693 or you can use the IP address itself).</p>
695 <p>Only one fetchmail option interacts directly with your IP
696 address, '<code>interface</code>'. This option can be used to set
697 the gateway device and restrict the IP address range fetchmail will
698 use. Such a restriction is sometimes useful for security reasons,
699 especially on multihomed sites. See <a href="#C3">C3</a>.</p>
701 <p>I recommend against trying to set up the <code>interface</code>
702 option when initially developing your poll configuration -- it's
703 never necessary to do this just to get a link working. Get the link
704 working first, observe the actual address range you see on
705 connections, and add an <code>interface</code> option (if you need
708 <p>You can't use ETRN if you have a dynamic IP address (your ISP
709 changes your IP address occasionally, possibly with every connect).
710 You need to have your own registered domain and a definite IP
711 address registered for that domain. The server needs to be
712 configured to accept mail for your domain but then queue it to
713 forward to your machine. ETRN just tells to server to flush its
714 queue for your domain. Fetchmail doesn't actually get the mail in
717 <p>You can use On-Demand Mail Relay (ODMR) with a dynamic IP
718 address; that's what it was designed for, and it provides
719 capabilities very similar to ETRN. Unfortunately ODMR servers are
720 not yet widely deployed, as of early 2001.</p>
722 <p>If you're using a dynamic-IP configuration, one other
723 (non-fetchmail) problem you may run into with outgoing mail is that
724 some sites will bounce your email because the hostname your giving
725 them isn't real (and doesn't match what they get doing a reverse
726 DNS on your dynamically-assigned IP address). If this happens, you
727 need to hack your sendmail so it masquerades as your host.
734 <p>in your <code>sendmail.cf</code> will work, or you can set</p>
737 MASQUERADE_AS(smarthost.here)
740 <p>in the m4 configuration and do a reconfigure. (In both cases,
741 replace <code>smarthost.here</code> with the actual name of your
742 mailhost.) See the <a
743 href="http://www.lege.com/sendmail-FAQ.txt">sendmail FAQ</a> for
747 <h2><a id="G12" name="G12">G12. Is any special configuration needed
748 to use firewalls?</a></h2>
750 <p>No. You can use fetchmail with SOCKS, the standard tool for
751 indirecting TCP/IP through a firewall. You can find out about
752 SOCKS, and download the SOCKS software including server and client
753 code, at the <a href="http://www.socks.nec.com/">SOCKS distribution
756 <p>The specific recipe for using fetchmail with a firewall is at <a
757 href="#K1">K1</a></p>
760 <h2><a id="G13" name="G13">G13. Is any special configuration needed
761 to <em>send</em> mail?</a></h2>
763 <p>A user asks: but how do we send mail out to the POP3 server? Do
764 I need to implement another tool or will fetchmail do this too?</p>
766 <p>Fetchmail only handles the receiving side. The sendmail or other
767 preinstalled MTA on your client machine will handle sending mail
768 automatically; it will ship mail that is submitted while the
769 connection is active, and put mail that is submitted while the
770 connection is inactive into the outgoing queue.</p>
772 <p>Normally, sendmail is also run periodically (every 15 minutes on
773 most Linux systems) in a mode that tries to ship all the mail in
774 the outgoing queue. If you have set up something like pppd to
775 automatically dial out when your kernel is called to open a TCP/IP
776 connection, this will ensure that the mail gets out.</p>
779 <h2><a id="G14" name="G14">G14. Is fetchmail
780 Y2K-compliant?</a></h2>
782 <p>Fetchmail is fully Y2K-compliant.</p>
784 <p>Fetchmail could theoretically have problems when the 32-bit
785 time_t counters roll over in 2038, but I doubt it. Timestamps
786 aren't used for anything but log entry generation. Anyway, if you
787 aren't running on a 64-bit machine by then, you'll deserve to
791 <h2><a id="G15" name="G15">G15. Is there a way in fetchmail to
792 support disconnected IMAP mode?</a></h2>
794 <p>No. Fetchmail is a mail transport agent, best understood as a
795 protocol gateway between POP3/IMAP servers and SMTP. Disconnected
796 operation requires an elaborate interactive client. It's a very
797 different problem.</p>
800 <h2><a id="G16" name="G16">G16. How will fetchmail perform under
801 heavy loads?</a></h2>
803 <p>Fetchmail streams message bodies line-by-line; the most core it
804 ever requires per message is enough memory to hold the RFC822
805 header, and that storage is freed when body processing begins. It
806 is, accordingly, quite economical in its use of memory.</p>
808 <p>After startup time, a fetchmail running in daemon mode stats its
809 configuration file once per poll cycle to see whether it has
810 changed and should be rescanned. Other than that, a fetchmail in
811 normal operation doesn't touch the disk at all; that job is left up
812 to the MTA or MDA the fetchmail talks to.</p>
814 <p>Fetchmail's performance is usually bottlenecked by latency on
815 the POP server or (less often) on the TCP/IP link to the server.
816 This is not a problem readily solved by tuning fetchmail, or even
817 by buying more TCP/IP capacity (which tends to improve bandwidth
818 but not necessarily latency).</p>
821 <h2><a id="B1" name="B1">B1. Make coughs and dies when building on
824 <p>The vendor-supplied make on FreeBSD systems can only be used
825 within FreeBSD's "scope", e.g. the ports collection. Type "gmake"
826 to run GNU make and better things will happen.</p>
829 <h2><a id="B2" name="B2">B2. Lex bombs out while building the
830 fetchmail lexer.</a></h2>
832 <p>In the immortal words of Alan Cox the last time this came up:
833 "Take the Solaris lex and stick it up the backside of a passing
834 Sun salesman, then install <a
835 href="ftp://ftp.gnu.org/pub/non-gnu/flex/">flex</a> and use that.
836 All will be happier."</p>
838 <p>I couldn't have put it better myself, and ain't going to try
841 <p>(The same problem has been reported under HP-UX v10.20 and
845 <h2><a id="B3" name="B3">B3. I get link failures when I try to
846 build fetchmail.</a></h2>
848 <p>If you get errors resembling these</p>
851 mxget.o(.text+0x35): undefined referenceto '__res_search'
852 mxget.o(.text+0x99): undefined reference to '__dn_skipname'
853 mxget.o(.text+0x11c): undefined reference to '__dn_expand'
854 mxget.o(.text+0x187): undefined reference to '__dn_expand'
855 make: *** [fetchmail] Error 1
858 <p>then you must add "-lresolv" to the LOADLIBS line in your
859 Makefile once you have installed the 'bind' package.</p>
861 <p>If you get link errors involving <tt>dcgettext</tt>, like
865 rcfile_y.o: In function 'yyparse':
866 rcfile_y.o(.text+0x3aa): undefined reference to 'dcgettext__'
867 rcfile_y.o(.text+0x4f2): undefined reference to 'dcgettext__'
868 rcfile_y.o(.text+0x5ee): undefined reference to 'dcgettext__'
869 rcfile_y.o: In function 'yyerror':
870 rcfile_y.o(.text+0xc7c): undefined reference to 'dcgettext__'
871 rcfile_y.o(.text+0xcc8): undefined reference to 'dcgettext__'
872 rcfile_y.o(.text+0xdf9): more undefined references to 'dcgettext__' follow
875 <p>reconfigure with <tt>configure --with-included-gettext</tt>.
876 This is due to some brain-damage in the GNU internationalization
880 <h2><a id="B4" name="B4">B4. I get build failures in the intl
883 <p>Reconfigure with <tt>--disable-nls</tt> and recompile.</p>
885 <p>GNU gettext is an overengineered, fragile pile of crap. I have
886 teetered on the brink of removing support for it entirely several
890 <h2><a id="F1" name="F1">F1. Why does my old .fetchmailrc file no
891 longer work?</a></h2>
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 'via localhost' special case for use with ssh tunnelling is
901 gone. Use the %h 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>
1018 <h2><a id="F2" name="F2">F2. The .fetchmailrc parser won't accept
1019 my all-numeric user name.</a></h2>
1021 <p>Either upgrade to a post-5.0.5 fetchmail or put string quotes
1024 <p>The configuration file parser in older fetchmail versions
1025 treated any all-numeric token as a number, which confused it when
1026 it was expecting a name. String quoting forces the token's
1029 <p>The lexical analyzer in 5.0.6 and beyond is smarter and assumes
1030 any token following "username" or "password" is a string.</p>
1033 <h2><a id="F3" name="F3">F3. The .fetchmailrc parser won't accept
1034 my host or username beginning with 'no'.</a></h2>
1036 <p>See <a href="#F2">F2</a>. You're caught in an unfortunate crack
1037 between the newer-style syntax for negated options ('no keep', 'no
1038 rewrite' etc.) and the older style run-on syntax ('nokeep',
1039 'norewrite' etc.).</p>
1041 <p>Upgrade to a 5.0.6 or later fetchmail, or put string quotes
1042 around your token.</p>
1045 <h2><a id="F4" name="F4">F4. I'm getting a 'parse error' message I
1046 don't understand.</a></h2>
1048 <p>The most common cause of mysterious parse errors is putting a
1049 server option after a user option. Check the manual page; you'll
1050 probably find that by moving one or more options closer to the
1051 'poll' keyword you can eliminate the problem.</p>
1053 <p>Yes, I know these ordering restrictions are hard to understand.
1054 Unfortunately, they're necessary in order to allow the 'defaults'
1055 feature to work.</p>
1058 <h2><a id="C1" name="C1">C1. Why do I need a .fetchmailrc when
1059 running as root on my own machine?</a></h2>
1061 <p>Ian T. Zimmerman <itz@rahul.net> asked:</p>
1063 <p>On the machine where I'm the only real user, I run fetchmail as
1064 root from a cron job, like this:</p>
1067 fetchmail -u "itz" -p POP3 -s bolero.rahul.net
1070 <p>This used to work as is (with no .fetchmailrc file in root's
1071 home directory) with the last version I had (1.7 or 1.8, I don't
1072 remember). But with 2.0, it RECPs all mail to the local root user,
1073 unless I create a .fetchmailrc in root's home directory
1077 skip bolero.rahul.net proto POP3
1081 <p>It won't work if the second line is just "<code>user
1082 itz</code>". This is silly.</p>
1084 <p>It seems fetchmail decides to RECP the 'default local user'
1085 (i.e. the uid running fetchmail) unless there are local aliases,
1086 and the 'default' aliases (itz->itz) don't count. They
1091 <p>No they shouldn't. I thought about this for a while, and I don't
1092 much like the conclusion I reached, but it's unavoidable. The
1093 problem is that fetchmail has no way to know, in general, that a
1094 local user 'itz' actually exists.</p>
1096 <p>"Ah!" you say, "Why doesn't it check the password file to see if
1097 the remote name matches a local one?" Well, there are two
1100 <p>One: it's not always possible. Suppose you have an SMTP host
1101 declared that's not the machine fetchmail is running on? You
1104 <p>Two: How do you know server itz and SMTP-host itz are the same
1105 person? They might not be, and fetchmail shouldn't assume they are
1106 unless local-itz can explicitly produce credentials to prove it
1107 (that is, the server-itz password in local-itz's .fetchmailrc
1110 <p>Once you start running down possible failure modes and thinking
1111 about ways to tinker with the mapping rules, you'll quickly find
1112 that all the alternatives to the present default are worse or
1113 unacceptably more complicated or both.</p>
1116 <h2><a id="C2" name="C2">C2. How can I arrange for a fetchmail
1117 daemon to get killed when I log out?</a></h2>
1119 <p>The easiest way to dispatch fetchmail on logout (which will work
1120 reliably only if you have just one login going at any time) is to
1121 arrange for the command 'fetchmail -q' to be called on logout.
1122 Under bash, you can arrange this by putting 'fetchmail -q' in the
1123 file '~/.bash_logout'. Most csh variants execute '~/.logout' on
1124 logout. For other shells, consult your shell manual page.</p>
1126 <p>Automatic startup/shutdown of fetchmail is a little harder to
1127 arrange if you may have multiple login sessions going. In the
1128 contrib subdirectory of the fetchmail distribution there is some
1129 shell code you can add to your .bash_login and .bash_logout
1130 profiles that will accomplish this. Thank James Laferriere
1131 <babydr@nwrain.net> for it.</p>
1133 <p>Some people start up and shut down fetchmail using the ppp-up
1134 and ppp-down scripts of pppd.</p>
1137 <h2><a id="C3" name="C3">C3. How do I know what interface and
1138 address to use with --interface?</a></h2>
1140 <p>This depends a lot on your local networking configuration (and
1141 right now you can't use it at all except under Linux and the newer
1142 BSDs). However, here are some important rules of thumb that can
1143 help. If they don't work, ask your local sysop or your Internet
1146 <p>First, you may not need to use --interface at all. If your
1147 machine only ever does SLIP or PPP to one provider, it's almost
1148 certainly by a point to point modem connection to your provider's
1149 local subnet that's pretty secure against snooping (unless someone
1150 can tap your phone or the provider's local subnet!). Under these
1151 circumstances, specifying an interface address is fairly
1154 <p>What the option is really for is sites that use more than one
1155 provider. Under these circumstances, typically one of your provider
1156 IP addresses is your mailserver (reachable fairly securely via the
1157 modem and provider's subnet) but the others might ship your packets
1158 (including your password) over unknown portions of the general
1159 Internet that could be vulnerable to snooping. What you'll use
1160 --interface for is to make sure your password only goes over the
1161 one secure link.</p>
1163 <p>To determine the device:</p>
1166 <li>If you're using a SLIP link, the correct device is probably
1169 <li>If you're using a PPP link, the correct device is probably
1172 <li>If you're using a direct connection over a local network such
1173 as an ethernet, use the command 'netstat -r' to look at your
1174 routing table. Try to match your mailserver name to a destination
1175 entry; if you don't see it in the first column, use the 'default'
1176 entry. The device name will be in the rightmost column.</li>
1179 <p>To determine the address and netmask:</p>
1182 <li>If you're talking to slirp, the correct address is probably
1183 10.0.2.15, with no netmask specified. (It's possible to configure
1184 slirp to present other addresses, but that's the default.)</li>
1186 <li>If you have a static IP address, run 'ifconfig <device>',
1187 where <device> is whichever one you've determined. Use the IP
1188 address given after "inet addr:". That is the IP address for your
1189 end of the link, and is what you need. You won't need to specify a
1192 <li>If you have a dynamic IP address, your connection IP will vary
1193 randomly over some given range (that is, some number of the least
1194 significant bits change from connection to connection). You need to
1195 declare an address with the variable bits zero and a complementary
1196 netmask that sets the range.</li>
1199 <p>To illustrate the rule for dynamic IP addresses, let's suppose
1200 you're hooked up via SLIP and your IP provider tells you that the
1201 dynamic address pool is 255 addresses ranging from 205.164.136.1 to
1202 205.164.136.255. Then</p>
1205 interface "sl0/205.164.136.0/255.255.255.0"
1208 <p>would work. To range over any value of the last two octets
1209 (65536 addresses) you would use</p>
1212 interface "sl0/205.164.0.0/255.255.0.0"
1216 <h2><a id="C4" name="C4">C4. How can I set up support for
1217 sendmail's anti-spam features?</a></h2>
1219 <p>This answer covers versions of sendmail from 8.9.3-20 (the
1220 version installed in Red Hat 6.2) upwards. If you have an older
1221 version, upgrade to sendmail 8.9.</p>
1223 <p>Stock sendmails can now do anti-spam exclusions based on a
1224 database of filter rules. The human-readable form of the database
1225 is at <tt>/etc/mail/access</tt>. The database itself is at
1226 <tt>/etc/mail/access.db</tt>.</p>
1228 <p>The table itself uses email addresses, domain names, and network
1229 numbers as keys. For example,</p>
1232 spammer@aol.com REJECT
1233 cyberspammer.com REJECT
1237 <p>would refuse mail from spammer@aol.com, any user from
1238 cyberspammer.com (or any host within the cyberspammer.com domain),
1239 and any host on the 192.168.212.* network. (This feature can be
1240 used to do other things as well; see the <a
1241 href="http://www.sendmail.org/m4/anti-spam.html">sendmail
1242 documentation</a> for details)</p>
1244 <p>To actually set up the database, run</p>
1247 makemap hash deny <deny
1250 <p>in /etc/mail.</p>
1252 <p>To test, send a message to your mailing address from that host
1253 and then pop off the message with fetchmail, using the -v argument.
1254 You can monitor the SMTP transaction, and when the FROM address is
1255 parsed, if sendmail sees that it is an address in spamlist,
1256 fetchmail will flush and delete it.</p>
1258 <p>Under no circumstances put your <strong>mailhost</strong> or
1259 <strong>any host you accept mail from</strong> using fetchmail into
1260 your reject file. You <strong>will</strong> lose mail if you do
1264 <h2><a id="C5" name="C5">C5. How can I poll some of my mailboxes
1265 more/less often than others?</a></h2>
1267 <p>Use the <cite>interval</cite> keyword on the ones that should be
1268 checked less often. For example, if you do a poll every 5 minutes,
1269 and want to poll some mailboxes every 5 minutes and some every 30
1270 minutes, use something like this:</p>
1273 poll mainsite.example.com proto pop3 user ....
1274 poll secondary.example.com proto pop3 interval 6 user ...
1277 <p>Then secondary.example.com will be polled every 6th time that
1278 mainsite.example.com is polled, which with a polling interval of
1279 every 5 minutes means that secondary.example.com will be polled
1280 every 30 minutes.</p>
1283 <h2><a id="C6" name="C6">Fetchmail works OK started up manually,
1284 but not from an init script.</a></h2>
1286 <p>Often, startup scripts have a different environment than an
1287 interactive login shell. For instance, $HOME might point to "/root"
1288 when you are logged in as root, but it might be either unset, or
1289 set to "/" when the startup scripts are running. That means
1290 fetchmail at startup can't find the .fetchmailrc.</p>
1292 <p>Pick a location (such as /etc/fetchmailrc) and use fetchmail's
1293 -f option to point fetchmail at it. That should solve the
1297 <h2><a id="C7" name="C7">C7. How can I forward mail to another
1300 <p>To forward mail to a host other than the one you are running
1301 fetchmail on, use the <code>smtphost</code> or
1302 <code>smtpname</code> option. See the manual page for details.</p>
1305 <h2><a id="T1" name="T1">T1. How can I use fetchmail with
1308 <p>For most sendmails, no special configuration is required. Eric
1309 Allman tells me that if <code>FEATURE(always_add_domain)</code> is
1310 included in sendmail's configuration, you can leave the
1311 <code>rewrite</code> option off.</p>
1313 <p>If your sendmail complains "sendmail does not relay", make
1314 sure your sendmail.cf file says <code>Cwlocalhost</code> so that
1315 sendmail recognizes 'localhost' as a name of its host.</p>
1317 <p>If you're mailing from another machine on your local network,
1318 also ensure that its IP address is listed in ip_allow or name in
1319 name_allow (usually in /etc/mail/)</p>
1321 <p>If you find that your sendmail doesn't like the address
1322 'FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail that
1323 fetchmail generates), you may have to set
1324 <code>FEATURE(accept_unqualified_senders)</code>.</p>
1326 <p>Günther Leber reports that Digital Unix sendmails won't
1327 work with fetchmail. The symptom is an error message "<code>553
1328 Local configuration error, hostname not recognized as
1329 local</code>". The problem is that fetchmail normally feeds
1330 sendmail with the client machine's host address in the MAIL FROM
1331 line. These sendmails think this means they're seeing the result of
1332 a mail loop and suppress the mail. You may be able to work around
1333 this by running in <code>--invisible</code> mode.</p>
1335 <p>If you want to support multidrop mode, and you can get access to
1336 your mailserver's sendmail.cf file, it's a good idea to add this
1340 H?l?Delivered-To: $h
1343 <p>This will cause the mailserver's sendmail to reliably write the
1344 appropriate envelope address into each message before fetchmail
1345 sees it, and tell fetchmail which header it is.  With this
1346 change, multidrop mode should work reliably even when the Received
1347 header omits the envelope address (which will typically be the case
1348 when the message has multiple recipients).  However it will
1349 still not distinguish the recipients, your only advantage is that
1350 no bounce will be sent if a message is BCC addressed to multiple
1351 users at your site.  To fix even that problem, you might want
1352 to try the following hack, which is however untested and quite
1356 H?J?Delivered-To: $u
1358 Mmdrop, P=/usr/bin/procmail, F=lsDFMqSPfhnu9J,
1359 S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP/HdrToSMTP,
1360 T=DNS/RFC822/X-Unix,
1361 A=procmail -Y -a $u -d $h
1364 <p>For both hacks, you have to declare '<code>envelope
1365 "Delivered-To:"</code>' on the fetchmail side, to put the virtual
1366 domain (e.g. 'domain.com') with RELAY permission into your access
1367 file and to add a line reading '<code>domain.com
1368 local:local-pop-user</code>' for the first and '<code>domain.com
1369 mdrop:local-pop-user</code>' for the second hack to your
1372 <p>You will notice that if the mail already has a Delivered-To
1373 header, sendmail will not add another.  Further, editing
1374 sendmail.cf directly is not very comfortable.  Solutions for
1375 both problems can be found in Peter 'Rattacresh' Backes' 'hybrid'
1376 patch against sendmail.  Have a look at it, you can find it in
1377 the contrib subdirectory.</p>
1379 <p>Feel free to try Martijn Lievaart's detailed recipe in the
1380 contrib subdirectory of the fetchmail source distribution, it
1381 attempts to realize multidrop mailboxes with an external
1384 <p>If for some reason you are invoking sendmail via the
1385 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
1386 don't forget to include the -i switch. Otherwise you will
1387 occasionally get mysterious delivery failures with a SIGPIPE as the
1388 sendmail instance dies. The problem is messages with a single dot
1389 at start of a text line.</p>
1392 <h2><a id="T2" name="T2">T2. How can I use fetchmail with
1395 <p>Turn on the <code>forcecr</code> option; qmail's listener mode
1396 doesn't like header or message lines terminated with bare
1399 <p>(This information is thanks to Robert de Bath
1400 <robert@mayday.cix.co.uk>.)</p>
1402 <p>If a mailhost is using the qmail package (see <a
1403 href="http://pobox.com/~djb/qmail.html">http://pobox.com/~djb/qmail.html</a>)
1404 then, providing the local hosts are also using qmail, it is
1405 possible to set up one fetchmail link to be reliably collect the
1406 mail for an entire domain.</p>
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. The major reason for this is to prevent mail
1414 <p>To set up qmail to batch mail for a disconnected site the
1415 ISP-mailhost will have normally put that site in its 'virtualhosts'
1416 control file so it will add a prefix to all mail addresses for this
1417 site. This results in mail sent to
1418 'username@userhost.userdom.dom.com' having a 'Delivered-To:' line
1422 Delivered-To: mbox-userstr-username@userhost.userdom.dom.com
1425 <p>A single host maildrop will be slightly simpler:</p>
1428 Delivered-To: mbox-userstr-username@userhost.dom.com
1431 <p>The ISP can make the 'mbox-userstr-' prefix anything they choose
1432 but a string matching the user host name is likely.</p>
1434 <p>To use this line you must:</p>
1437 <li>Ensure the option 'envelope Delivered-To:' is in the fetchmail
1440 <li>Ensure you have a localdomains containing 'userdom.dom.com' or
1441 'userhost.dom.com' respectively.</li>
1444 <p>So far this reliably delivers messages to the correct machine of
1445 the local network, to deliver to the correct user the
1446 'mbox-userstr-' prefix must be stripped off of the user name. This
1447 can be done by setting up an alias within the qmail MTA on each
1448 local machine. Simply create a dot-qmail file called
1449 '.qmail-mbox-userstr-default' in the alias directory (normally
1450 /var/qmail/alias) with the contents:</p>
1453 | ../bin/qmail-inject -a -f"$SENDER" "${LOCAL#mbox-userstr-}@$HOST"
1456 <p>Note this <em>does</em> require a modern /bin/sh.</p>
1458 <p>Peter Wilson adds:</p>
1460 <p>"My ISP uses "alias-unzzippedcom-" as the prefix, which means
1461 that I need to name my file ".qmail-unzzippedcom-default". This is
1462 due to qmail's assumption that a message sent to user-xyz is
1463 handled by the file ~user/.qmail-xyz (or
1464 ~user/.qmail-default)."</p>
1466 <p>Luca Olivetti adds:</p>
1468 <p>If you aren't using qmail locally, or you don't want to set up
1469 the alias mechanism described above, you can use the option
1470 '<code>qvirtual "mbox-userstr-"</code>' in your fetchmail config
1471 file to strip the prefix from the local user name.</p>
1474 <h2><a id="T3" name="T3">T3. How can I use fetchmail with
1477 <p>If you have <code>rewrite</code> on:</p>
1479 <p>There is an RFC1123 requirement that MAIL FROM and RCPT TO
1480 addresses you pass to it have to be canonical (e.g. with a fully
1481 qualified hostname part). Therefore fetchmail tries to pass fully
1482 qualified RCPT TO addresses. But exim does not by default accept
1483 'localhost' as a fully qualified domain. This can be fixed.</p>
1485 <p>In exim.conf, add 'localhost' to your local_domains declaration
1486 if it's not already present. For example, the author's site at
1487 thyrsus.com would have a line reading:</p>
1490 local_domains = thyrsus.com:localhost
1493 <p>If you have <code>rewrite</code> off:</p>
1495 <p>MAIL FROM is a potential problem if the MTAs upstream from your
1496 fetchmail don't necessarily pass canonicalized From and Return-Path
1497 addresses, and fetchmail's <code>rewrite</code> option is off. The
1498 specific case where this has come up involves bounce messages
1499 generated by sendmail on your mailer host, which have the
1500 (un-canonicalized) origin address MAILER-DAEMON.</p>
1502 <p>The right way to fix this is to enable the <code>rewrite</code>
1503 option and have fetchmail canonicalize From and Return-Path
1504 addresses with the mailserver hostname before exim sees them. This
1505 option is enabled by default, so it won't be off unless you turned
1508 <p>If you must run with <code>rewrite</code> off, there is a switch
1509 in exim's configuration files that allows it to accept domainless
1510 MAIL FROM addresses; you will have to flip it by putting the
1514 sender_unqualified_hosts = localhost
1517 <p>in the main section of the exim configuration file. Note that
1518 this will result in such messages having an incorrect domain name
1519 attached to their return address (your SMTP listener's hostname
1520 rather than that of the remote mail server).</p>
1523 <h2><a id="T4" name="T4">T4. How can I use fetchmail with
1526 <p>Smail 3.2 is very nearly plug-compatible with sendmail, and may
1527 work fine out of the box.</p>
1529 <p>We have one report that when processing multiple messages from a
1530 single fetchmail session, smail sometimes delivers them in an order
1531 other than received-date order. This can be annoying because it
1532 scrambles conversational threads. This is not fetchmail's problem,
1533 it is an smail 'feature' and has been reported to the maintainers
1536 <p>Very recent smail versions require an
1537 <code>-smtp_hello_verify</code> option in the smail config file.
1538 This overrides smail's check to see that the HELO address is
1539 actually that of the client machine, which is never going to be the
1540 case when fetchmail is in the picture. According to RFC1123 an SMTP
1541 listener <em>must</em> allow this mismatch, so smail's new behavior
1542 (introduced sometime between 3.2.0.90 and 3.2.0.95) is a bug.</p>
1544 <p>You may also need to say
1545 <code>-smtp_hello_broken_allow=127.0.0.1</code> in order for smail
1546 to accept the "localhost" that fetchmail normally appends to
1547 recipient addresses.</p>
1550 <h2><a id="T5" name="T5">T5. How can I use fetchmail with SCO's
1553 <p>MMDF itself is difficult to configure, but it turns out that
1554 connecting fetchmail to MMDF's SMTP channel isn't that hard. You
1556 href="http://www.aplawrence.com/Unixart/uucptofetch.html">MMDF
1557 recipe</a> that describes replacing a UUCP link with fetchmail
1561 <h2><a id="T6" name="T6">T6. How can I use fetchmail with Lotus
1564 <p>The Lotus Notes SMTP gateway tries to deduce when it should
1565 convert \n to \r\n, but its rules are not the intuitive and
1566 correct-for-RFC822 ones. Use 'forcecr'.</p>
1569 <h2><a id="T7" name="T7">T7. How can I use fetchmail with Courier
1572 <p>The courier mta doesn't like RCPT addresses that look like
1573 <code>someone@localhost</code>. Work around this with an
1574 <code>smtphost</code> or <code>smtpaddress</code>.</p>
1577 <h2><a name="T8">T8. How can I use fetchmail with vbmailshield?</a></h2>
1579 <p>vbmailshield's SMTP interpreter is broken. It doesn't understand RSET.</p>
1581 <p>As a workaround, you can set batchlimit to 1 so RSET is never used.</p>
1584 <h2><a id="S1" name="S1">S1. How can I use fetchmail with
1587 <p>Qualcomm's qpopper is probably the best-of-breed among POP3
1588 servers, and is very widely deployed. Nevertheless, it has some
1589 problems which fetchmail exposes. We recommend using <a
1590 href="#G8">IMAP</a> instead if at all possible. If you must talk to
1591 qpopper, here are some problems to be aware of:</p>
1593 <h3>Problems with retrieving large messages from qpopper 2.53</h3>
1596 href="mailto:tony@atn.com.hk"><tony@atn.com.hk></a> reports
1597 that there is a bad intercation between fetchmail and qpopper 2.5.3
1598 under Red Hat Linux versions 5.0 to 5.2, kernels 2.0.34 to 2.0.35.
1599 When fetching very large messages (over 700K) from 2.5.3, fetchmail
1600 will hang with a socket error.</p>
1602 <p>This is probably not a fetchmail bug, but rather a symptom of
1603 some problem in the networking stack that qpopper's transmission
1604 pattern is tickling, as fetchpop (another Linux POP client) also
1605 displays the hang but Netscape running under Win95 does not. The
1606 problem can also be banished by <a
1607 href="http://www.eudora.com/freeware/qpop.html">upgrading to
1608 qpopper 3.0b1</a>.</p>
1610 <h3>Bad interaction with fetchmail 4.4.2 to 4.4.7</h3>
1612 <p>Versions of fetchmail from 4.4.2 through 4.4.7 had a bad
1613 interaction with Eudora qpopper versions 2.3 and later. See <a
1614 href="#X5">X5</a> for details. The solution is to upgrade your
1618 <h2><a id="S2" name="S2">S2. How can I use fetchmail with Microsoft
1621 <p>It's been reliably reported that Exchange 2000's POP3 support is
1622 so broken that it's unusable. One symptom is that messages without
1623 a terminating newline get the POP3 message termination dot emitted
1624 -- you guessed it -- right after the last character of the message,
1625 with no terminating newline added. This will hang fetchmail or any
1626 other RFC-compliant server. IMAP is alleged to work OK, though.</p>
1628 <p>Older versions of Exchange are semi-usable. They randomly drop
1629 attachments on the floor, though. Microsoft acknowledges this
1630 as a known bug and apparently has no plans to fix it.</p>
1632 <p>Fetchmail using IMAP supports the proprietary NTLM mode used
1633 with M$ Exchange servers. To enable this, configure fetchmail with
1634 the --enable-NTLM option and recompile it. Specify a user option
1635 value that looks like 'user@domain': the part to the left of the @
1636 will be passed as the username and the part to the right as the
1639 <p>M$ Exchange violates the POP3 and IMAP RFCs. Its LIST command
1640 does not reveal the real sizes of mail in the pop mailbox, but the
1641 sizes of the compressed versions in the exchange mail database
1642 (thanks to Arjan De Vet and Guido Van Rooij for alerting us to this
1645 <p>Fetchmail works with M$ Exchange, despite this brain damage. Two
1646 features are compromised. One is that the --limit option will not
1647 work right (it will check against compressed and not actual sizes).
1648 The other is that a too-small SIZE argument may be passed to your
1649 ESMTP listener, assuming you're using one (this should not be a
1650 problem unless the actual size of the message is above the
1651 listener's configured length limit).</p>
1653 <p>Somewhat belatedly, I've learned that there's supposed to be a
1654 registry bit that can fix this breakage:</p>
1657 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1658 System\Pop3 Compatibility
1661 <p>This is a bitmask that controls the variations from the standard
1662 protocol. The bits defined are:</p>
1665 <dt>0x00000001:</dt>
1667 <dd>Report exact message sizes for the LIST command</dd>
1669 <dt>0x00000002:</dt>
1671 <dd>Allow arbitrary linear whitespace between commands and
1674 <dt>0x00000004:</dt>
1676 <dd>Enable the LAST command</dd>
1678 <dt>0x00000008:</dt>
1680 <dd>Allow an empty PASS command (needed for users with blank
1681 passwords, but illegal in the protocol)</dd>
1683 <dt>0x00000010:</dt>
1685 <dd>Relax the length restrictions for arguments to commands
1686 (protocol requires 40, but some user names may be longer than
1689 <dt>0x00000020:</dt>
1691 <dd>Allow spaces in the argument to the USER command.</dd>
1694 <p>There's another one that may be useful to know about:</p>
1697 KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1698 System\Pop3 Performance
1702 <dt>0x00000001:</dt>
1704 <dd>Render messages to a temporary stream instead of sending
1705 directly from the database (should always be on)</dd>
1707 <dt>0x00000002: Flag unrenderable messages (instead of just failing
1708 commands) (should only be on if you are seeing the problems
1709 reported in KB Q168109)</dt>
1711 <dt>0x00000004:</dt>
1713 <dd>Return from the QUIT command before all messages have been
1717 <p>The Microsoft pod-person who revealed this information to me
1718 admitted that he couldn't find it anywhere in their public
1721 <p>Another specific problem we have seen with Exchange servers has
1722 as its symptom a response to LOGIN that says "NO Ambiguous Alias".
1723 Grant Edwards writes:</p>
1725 <p>This means that Exchange Server is too f*&#ing stupid to
1726 figure out which mailbox belongs to you. Instead of actually
1727 keeping track of which inbox belongs to which user, it uses some
1728 half-witted, guess-o-matic heuristic to try to guess your mailbox
1729 name from your username.</p>
1731 <p>In your case it doesn't work because your username maps to more
1732 than one mailbox. For some people it doesn't work because their
1733 username maps to zero mailboxes. This is yet another inept, lame,
1734 almost criminally negligent design decision from our friends in
1737 <p>You've got several options:</p>
1740 <li>Get your administrator to configure the server so that
1741 usernames and mailbox names are the same.</li>
1743 <li>Get your administrator to add an alias that maps your username
1744 explicitly to your mailbox name.</li>
1747 <p>But, the best option involves a tactical nuclear weapon (an old
1748 ASROC will do), pissing off a lot people who live downwind from
1749 Redmond, and your choice of any Linux, NetBSD, FreeBSD, or Solaris
1753 <h2><a id="S3" name="S3">S3. How can I use fetchmail with HP
1756 <p>No special configuration is required, but OpenMail versions
1757 prior to 6.0 have an annoying bug similar to the big one in <a
1758 href="#S2">Microsoft Exchange</a>. The message sizes it gives in
1759 the LIST are rounded to the nearest 1024 bytes. It also has a nasty
1760 habit of discarding headers it doesn't recognize, such as X- and
1761 Resent- headers.</p>
1763 <p>As with M$ Exchange, the only real fix for these problems is to
1764 get a POP (or preferably IMAP) server that isn't brain-dead.
1765 OpenMail's project manager claims these bugs have been fixed in
1768 <p>We've had a more recent report (December 2001) that the TOP
1769 command fails, returning only one line regrardless of its argument,
1770 on something identifying itself as "OpenMail POP3 interface".</p>
1773 <h2><a id="S4" name="S4">S4. How can I use fetchmail with Novell GroupWise?</a></h2>
1775 <p>The Novell GroupWise IMAP server would be better named
1776 GroupFoolish; it is (according to the designer of IMAP) unusably
1777 broken. Among other things, it doesn't include a required content
1778 length in its BODY[TEXT] response.</p>
1780 <p>Fetchmail works around this problem, but we strongly recommend
1781 voting with your dollars for a server that isn't brain-dead. If you
1782 stick with code as shoddy as GroupWise seems to be, you will
1783 probably pay for it with other problems.</p>
1786 <h2><a id="S5" name="S5">S5. How can I use fetchmail with
1787 InterChange?</a></h2>
1789 <p>You can't. At least not if you want to be able to see
1790 attachments. InterChange has a bug similar to the MailMax server;
1791 it reports the message length with attachments but doesn't download
1792 them on TOP or RETR.</p>
1794 <p>On Jan 9 2001, the people at InfiniteMail sent me mail informing
1795 me that their new 3.61.08 release of InterChange fixes this
1796 problem. I don't have any reports one way or the other yet.</p>
1799 <h2><a id="S6" name="S6">S6. How can I use fetchmail with MailMax?</a></h2>
1801 <p>You can't. At least not if you want to be able to see
1802 attachments. MailMax has a bug; it reports the message length with
1803 attachments but doesn't download them on TOP or RETR.</p>
1805 <p>Also, we're told that TOP sometimes fails to retrieve the entire
1806 message even when enough lines have been specified. The MailMax
1807 developers have acknowledged this bug as of 4 May 2000, but there
1808 is no fix yet. If you must use this server, force RETR with the
1809 <tt>fetchall</tt> option.</p>
1812 <h2><a id="S7" name="S7">S7. How can I use fetchmail with FTGate?</a></h2>
1814 <p>The FTGate V2 server (and possibly older versions as well) has a
1815 weird bug. It answers OK twice to a TOP request! Use the
1816 <code>fetchall</code> option to force use of RETR and work around
1820 <h2><a id="I1" name="I1">I1. How can I use fetchmail with CompuServe RPA?</a></h2>
1822 <p>First, make sure your fetchmail has the RPA support compiled in.
1823 Stock fetchmail binaries (such as you might get from an RPM) don't.
1824 You can check this by looking at the output of <code>fetchmail
1825 -V</code>; if you see the string "+RPA" after the version ID you're
1826 good to go, otherwise you'll have to build your own from sources
1827 (see the INSTALL file in the source distribution for
1830 <p>Give your CompuServe pass-phrase in lower case as your password.
1831 Add '@compuserve.com' to your user ID so that it looks like 'user
1832 <UserID>@compuserve.com', where <UserID> can be either
1833 your numerical userID or your E-mail nickname. An RPA-enabled
1834 fetchmail will automatically check for csi.com in the POP server's
1835 greeting line. If that's found, and your user ID ends with
1836 '@compuserve.com', it will query the server to see if it is
1837 RPA-capable, and if so do an RPA transaction rather than a
1838 plain-text password handshake.</p>
1840 <p><strong>Warning:</strong> the debug (-v -v) output of fetchmail
1841 will show your pass-phrase in Unicode!</p>
1843 <p>These two .fetchmailrc entries show the difference between an
1844 RPA and non-RPA configuration:</p>
1847 # This version will use RPA
1848 poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1849 user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
1850 is LOCAL_USER here options fetchall stripcr
1852 # This version will not use RPA
1853 poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1854 user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
1855 is LOCAL_USER here options fetchall stripcr
1859 <h2><a id="I2" name="I2">I2. How can I use fetchmail with Demon
1860 Internet's SDPS?</a></h2>
1862 <h3>Single-drop mode</h3>
1864 <p>You can get fetchmail to download the email for just one user
1865 from Demon Internet's POP3 server by giving it a username
1866 consisting of your Demon user name followed by your account name,
1867 with an at-sign between them.</p>
1869 <p>For example, to download email for the user
1870 <philh@vision25.demon.co.uk>, you could use the following
1871 .fetchmailrc file:</p>
1874 set postmaster "philh"
1875 poll pop3.demon.co.uk with protocol POP3:
1876 user "philh@vision25" is philh
1879 <h3>Multi-drop mode</h3>
1881 <p>Demon Internet's SDPS service is an implementation of POP3. All
1882 messages have a Received: header added when they enter the
1883 maildrop, like this:</p>
1886 Received: from punt-1.mail.demon.net by mailstore for fred@xyz.demon.co.uk
1887 id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
1890 <p>To enable multi-drop mode you need to tell fetchmail that
1891 'mailstore' is the name of the host which accepted the mail, and
1892 let it know the hostname part(s) of your E-mail address. The
1893 following example assumes that your hostname is xyz.demon.co.uk,
1894 and that you have also bought "mail forwarding" for the domain
1895 my-company.co.uk (in which case your MTA must also be configured to
1896 accept mail sent to user@my-company.co.uk)</p>
1899 poll pop3.demon.co.uk proto pop3 aka mailstore no dns:
1900 localdomains xyz.demon.co.uk my-company.co.uk
1904 <p>Note that Demon may delete mail on the server which is more than
1905 30 days old; see their <a
1906 href="http://www.demon.net/helpdesk/products/mail/sdps-tech.shtml">POP3
1907 page</a> for details.</p>
1909 <h3>The SDPS extension</h3>
1911 <p>There's a different way to do multidrop. It's not necessary on
1912 Demon Internet, since fetchmail can parse Received addresses, but
1913 the person who implemented this didn't know that. It may be useful
1914 if Demon Internet ever changes mail transports.</p>
1916 <p>SDPS includes a non-standard extension for retrieving the
1917 envelope of a message (*ENV), which fetchmail optionally supports
1918 if compiled with the --enable-SDPS option. If you have it, the
1919 first line of the fetchmail -V response will include the string
1922 <p>Once you have SDPS compiled in, fetchmail in POP3 mode will
1923 automatically detect when it's talking to a Demon Internet host in
1924 multidrop mode, and use the *ENV extension to get an envelope To
1927 <p>The autodetection works by looking at the hostname in the POP3
1928 greeting line; if you're accessing Demon Internet through a proxy
1929 it may fail. To force SDPS mode, pick "sdps" as your protocol.</p>
1932 <h2><a id="I3" name="I3">I3. How can I use fetchmail with usa.net's
1935 <p>Enable '<code>fetchall</code>'. A user reports that the 2.2
1936 version of USA.NET's POP server reports that you must use the
1937 '<code>fetchall</code>' option to make sure that all of the mail is
1938 retrieved, otherwise some may be left on the server. This is almost
1939 certainly a server bug.</p>
1941 <p>The usa.net servers (at least in their 2.2 version, June 1998)
1942 don't handle the TOP command properly, either. Regardless of the
1943 argument you give it, they retrieve only about 10 lines of the
1944 message. Fetchmail normally uses TOP for message retrieval in order
1945 to avoid marking messages seen, but '<code>fetchall</code>' forces
1946 it to use RETR instead.</p>
1948 <p>Also, we're told USA.NET adds a ton of hops to your messages.
1949 You may need to raise the MaxHopCount parameter in your sendmail.cf
1950 to avoid having fetched mail rejected.</p>
1952 <p>(Note: Other failure modes have been reported on usa.net's
1953 servers. They seem to be chronically flaky. We recommend finding
1954 another provider.)</p>
1957 <h2><a id="I4" name="I4">I4. How can I use fetchmail with geocities
1958 POP3 servers?</a></h2>
1960 <p>Nathan Cutler reports that the the mail.geocities.com POP3
1961 servers fail to include the first Received line of the message in
1962 the send to fetchmail. This can solve problems if your MUA
1963 interprets Received continuations as body lines and doesn't parse
1964 any of the following headers.</p>
1966 <p>Workaround is to use "mda" keyword or "-mda" switch:</p>
1969 mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
1972 <p>Replace \t with exactly one tabulation character.</p>
1974 <p>You should also consider using "fetchall" option because
1975 Geocities' servers sometimes think that the first 45 messages have
1976 already been read.</p>
1978 <p>Fix: Get an email provider that doesn't suck. The pop-up ads on
1979 Geocities are lame, you should boycott them anyway.</p>
1982 <h2><a id="I5" name="I5">I5. How can I use fetchmail with Hotmail or Lycos Webmail?</a></h2>
1984 <p>You can't directly. But you can use fetchmail with hotmail or lycos
1985 webmail with the help of the <a
1986 href='http://people.freenet.de/courierdave/'>HotWayDaemon</a>
1987 daemon. You don't even need to install hotwayd as a daemon in
1988 <samp>inetd.conf</samp> but can use it as a plugin. Your
1989 configuration should look like this:</p>
1992 poll localhost protocol pop3 tracepolls
1993 plugin "/usr/local/sbin/hotwayd -l 0 -p yourproxy:yourproxyport"
1994 username "youremail@hotmail.com" password "yourpassword"
1998 <p>As a second option you may consider using <a
1999 href="http://linux.cudeso.be/linuxdoc/gotmail.php">gotmail</a>.</p>
2002 <h2><a id="I6" name="I6">I6. How can I use fetchmail with MSN?</a></h2>
2004 <p>You can't. MSN uses something that looks like POP3, except the
2005 authentication part is nonstandard. And of course they don't
2006 document it, so nobody but their Windows clients can speak it.</p>
2008 <p>This is a customer lock-in tactic; we recommend boycotting MSN
2009 as the only appropriate response.</p>
2011 <p>As of 5.0.8, we have support for the client side of NTLM
2012 authentication. It's possible this may enable fetchmail to talk to
2013 MSN; if so, somebody should report it so this FAQ can be
2017 <h2><a id="I7" name="I7">I7. How can I use fetchmail with SpryNet?</a></h2>
2019 <p>The SpryNet POP3 servers mark a message queried with TOP as
2020 seen. This means that if your connection drops in mid-message, it
2021 may end up invisibly stuck on your mail spool. Use the
2022 <code>fetchall</code> flag to ensure that it's recovered on the
2026 <h2><a id="I8" name="I8">I8. How can I use fetchmail with comcast.net?</a></h2>
2028 <p>Stock fetchmail will work with a comcast.net server...<em>but</em>
2029 the Maillennium POP3 server comcat uses seems to have an 80K limit on
2030 the length of downloaded messages if you use POP3 TOP to retrieve.
2031 Anything larger is silently truncated. Don't mistake this for a
2032 fetchmail bug. (Reported July 2003.)</p>
2034 <p>Workaround: use the <tt>fetchall</tt> option.</p>
2037 <h2><a id="K1" name="K1">K1. How can I use fetchmail with SOCKS?</a></h2>
2039 <p>Giuseppe Guerini added a --with-socks option that supports
2040 linking with socks library. If you specify the value of this option
2041 as "yes", the configure script will try to find the Rconnect
2042 library and set the makefile up to link it. You can also specify a
2043 directory containing the Rconnect library.</p>
2045 <p>Alan Schmitt has added a similar --with-socks5 option that may
2046 work better if you have a recent version of the SOCKS library.</p>
2049 <h2><a id="K2" name="K2">K2. How can I use fetchmail with IPv6 and
2052 <p>To use fetchmail with IPv6, you need a system that supports
2053 IPv6, the "Basic Socket Interface Extensions for IPv6" (RFC 2133).
2056 <p>The NRL IPv6+IPsec software distribution can be obtained from:
2058 href="http://web.mit.edu/network/isakmp">http://web.mit.edu/network/isakmp</a></p>
2060 <p>More information on using IPv6 with Linux can be obtained
2065 href="http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html">
2066 http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html</a></li>
2070 <h2><a id="K3" name="K3">K3. How can I get fetchmail to work with
2073 <p>Use the <tt>plugin</tt> option. This is dead simple with
2077 plugin "ssh %h /usr/sbin/imapd"
2080 <p>You may have to use a different absolute pathname, whatever the
2081 location of imapd on your mailserver is. This option tells
2082 fetchmail that instead of opening a connection on the server's port
2083 143 and doing standard IMAP authentication, fetchmail should ssh to
2084 the server and run imapd, using the more secure ssh authentication
2085 (as well as getting ssh's end-to-end encryption). Most IMAP daemons
2086 will detect that they've been called from the command line and
2087 assume the connection is preauthenticated.</p>
2089 <p>POP3 daemons aren't quite as smart. They won't know they are
2090 preauthenticated in this mode, so you'll actually have to ship your
2091 password. It will be under ssh encryption, though, so that
2092 shouldn't be a problem.</p>
2095 <h2><a id="K4" name="K4">K4. What do I have to do to use the
2096 IMAP-GSS protocol?</a></h2>
2098 <p>Fetchmail can use RFC1731 GSSAPI authorization to safely
2099 identify you to your IMAP server, as long as you can share Kerberos
2100 V credentials with your mail host and you have a GSSAPI-capable
2101 IMAP server. UW-IMAP (available via FTP at <a
2102 href="ftp://ftp.cac.washington.edu/mail/">ftp.cac.washington.edu</a>)
2103 is the only one I'm aware of and the one I recommend anyway for
2104 other reasons. You'll need version 4.1-FINAL or greater though, and
2105 it has to have GSS support compiled in.</p>
2107 <p>Neither UW-IMAP nor fetchmail compile in support for GSS by
2108 default, since it requires libraries from the Kerberos V
2109 distribution (available via FTP at <a
2110 href="ftp://athena-dist.mit.edu/pub/ATHENA/kerberos">athena-dist.mit.edu</a>).
2111 If you have these, compiling in GSS support is simple: add a
2112 <code>--with-gssapi=[/path/to/krb5/root]</code> option to
2113 configure. For instance, I have all of my Kerberos V libraries
2114 installed under /usr/krb5 so I run <code>configure
2115 --with-gssapi=/usr/krb5</code></p>
2117 <p>Setting up Kerberos V authentication is beyond the scope of this
2118 FAQ (you may find Jim Rome's paper <a
2119 href="http://www.ornl.gov/~jar/HowToKerb.html">How to Kerberize
2120 your site</a> helpful), but you'll at least need to add a
2121 credential for imap/[mailhost] to the keytab of the mail server
2122 (IMAP doesn't just use the host key). Then you'll need to have your
2123 credentials ready on your machine (cf. kinit).</p>
2125 <p>After that things are very simple. Set your protocol to imap-gss
2126 in your .fetchmailrc, and omit the password, since imap-gss doesn't
2127 need one. You can specify a username if you want, but this is only
2128 useful if your mailbox belongs to a username different from your
2129 Kerberos principal.</p>
2131 <p>Now you don't have to worry about your password appearing in
2132 cleartext in your .fetchmailrc, or across the network.</p>
2135 <h2><a id="K5" name="K5">K5. How can I use fetchmail with
2138 <p>You'll need to have the <a
2139 href="http://www.openssl.org/">OpenSSL</a> libraries installed.
2140 Configure with --with-ssl. If you have the OpenSSL libraries
2141 installed in the default location (/usr/local/ssl) ths will
2142 suffice. If you have them installed in a non-default location,
2143 you'll need to specify it as an argument to --with-ssl after an
2146 <p>Note that there is a known bug in the implementation of SSL_peek
2147 under OpenSSL versions 0.9.5 and older that fetchmail occasionally
2148 tripped over, causing hangs. It is recommended that you install
2151 <p>Fetchmail binaries built this way support <code>ssl</code>,
2152 <code>sslkey</code>, and <code>sslcert</code> options that control
2153 SSL encryption. You will need to have an SSL-enabled mailserver to
2154 use these options. See the manual page for details and some words
2155 of care on the limited security provided.</p>
2157 <p>If your open OpenSSL session dies with a message that complains
2158 "PRNG not seeded", update or improve your operating system. This
2159 means that the OpenSSL library on your machine has been unable to
2160 locate a source of random bits from which to seed its random-number
2161 generator; normally these come from the <tt>/dev/urandom</tt>, and
2162 this message probably means your OS doesn't have that device.</p>
2164 <p>An interactive program could seed the random number generator
2165 from keystroke timings or some other form of user input. Because
2166 fetchmail is primarily designed to run forever as a background
2167 daemon, that option is not available in this case.</p>
2169 <p>If you don't have the libraries installed, but do have the
2170 OpenSSL utility toolkit, something like this may work:</p>
2173 poll MYSERVER port 993 plugin "openssl s_client -connect %h:%p"
2174 protocol imap username MYUSERNAME password MYPASSWORD
2177 <p>You should note that SSL is only secure against a "man-in-the-middle"
2178 attack if the client is able to verify that the peer's public key is the
2179 correct one, and has not been substituted by an attacker. fetchmail can do
2180 this in one of two ways: by verifying the SSL certificate, or by checking
2181 the fingerprint of the peer's public key.</p>
2183 <p>There are three parts to SSL certificate verification: checking that the
2184 domain name in the certificate matches the hostname you asked to connect to;
2185 checking that the certificate expiry date has not passed; and checking that
2186 the certificate has been signed by a known Certificate Authority (CA). This
2187 last step takes some preparation, as you need to install the root
2188 certificates of all the CA's which you might come across.</p>
2190 <p>The easiest way to do this is using the root CA keys supplied in the
2191 OpenSSL distribution, which means you need to download and unpack the
2192 source tarball from www.openssl.org. Once you have done that:</p>
2195 <li><code>mkdir /etc/ssl/certs</code></li>
2196 <li>in the openssl-x.x.x/certs directory: <code>cp *.pem /etc/ssl/certs/</code></li>
2197 <li>in the openssl-x.x.x/tools directory: edit c_rehash and set
2198 <code>$dir="/etc/ssl"</code></li>
2199 <li>run "perl c_rehash". This generates a number of symlinks within the
2200 /etc/ssl/certs/ directory</li>
2203 <p>Now in .fetchmailrc, set option sslcertpath to point to this
2207 poll pop3.example.com proto pop3 uidl no dns
2208 user foobar@example.com password xyzzy is foobar ssl sslcertpath /etc/ssl/certs
2211 <p>If the server certificate has not been signed by a known CA (e.g. it is a
2212 self-signed certificate), then this certificate validation will always
2215 <p>Certificate verification is always attempted. If it fails, by default a
2216 warning is printed but the connection carries on (which means you are not
2217 protected against attack). If your server's certificate has been properly
2218 set up and verifies correctly, then add the "sslcertck" option to enforce
2219 validation. If your server doesn't have a valid certificate though (e.g. it
2220 has a self-signed certificate) then it will never verify, and the only way
2221 you can protect yourself is by checking the fingerprint.</p>
2223 <p>To check the peer fingerprint: first use fetchmail -v once to connect to
2224 the host, at a time when you are pretty sure that there is no attack in
2225 progress (e.g. you are not traversing any untrusted network to reach the
2226 server). Make a note of the fingerprint shown. Now embed this in your
2227 .fetchmailrc using the sslfingerprint option: e.g.</p>
2230 poll pop3.example.com proto pop3 uidl no dns
2231 user foobar@example.com password xyzzy is foobar ssl sslfingerprint "67:3E:02:94:D3:5B:C3:16:86:71:37:01:B1:3B:BC:E2"
2234 <p>When you next connect, the public key presented by the server will be
2235 verified against the fingerprint given. If it's different, it may mean that
2236 a man-in-the-middle attack is in progress - or it might just mean that the
2237 server changed its key. It's up to you to determine which has happened.</p>
2240 <h2><a id="K6" name="K6">K6. How can I tell fetchmail not to use TLS
2241 if the server advertises it?</a></h2>
2243 <p>Some servers advertise STLS (POP3) or STARTTLS (IMAP), and fetchmail
2244 will automatically attempt TLS negotiation if SSL was enabled at compile
2245 time. This can however cause problems if the upstream didn't configure
2246 his certificates properly.</p>
2248 <p>In order to prevent fetchmail from trying TLS (STLS, STARTTLS)
2249 negotiation, add this option:</p>
2251 <pre>sslproto ssl23</pre>
2253 <p>This restricts fetchmail's SSL/TLS protocol choice from the default
2254 "SSLv2, SSLv3, TLSv1" to the two SSL variants, disabling TLSv1. Note
2255 however that this causes the connection to be unencrypted unless an
2256 encrypting "plugin" is used or SSL is requested explicitly.</p>
2259 <h2><a id="R1" name="R1">R1. Fetchmail isn't working, and -v shows
2260 'SMTP connect failed' messages.</a></h2>
2262 <p>Fetchmail itself is probably working, but your SMTP port 25
2263 listener is down or inaccessible.</p>
2265 <p>The first thing to check is if you can telnet to port 25 on your
2266 smtp host (which is normally 'localhost' unless you've specified an
2267 smtp option in your .fetchmailrc or on the command line) and get a
2268 greeting line from the listener. If the SMTP host is inaccessible
2269 or the listener is down, fix that first.</p>
2271 <p>In Red Hat Linux 6.x, SMTP is disabled by default. To fix this,
2272 set "DAEMON=yes" in your /etc/sysconfig/sendmail file, then restart
2273 sendmail by running "/sbin/service sendmail restart".</p>
2275 <p>If the listener seems to be up when you test with telnet, the
2276 most benign and typical problem is that the listener had a
2277 momentary seizure due to resource exhaustion while fetchmail was
2278 polling it -- process table full or some other problem that stopped
2279 the listener process from forking. If your SMTP host is not
2280 'localhost' or something else in /etc/hosts, the fetchmail glitch
2281 could also have been caused by transient nameserver failure.</p>
2283 <p>Try running fetchmail -v again; if it succeeds, you had one of
2284 these kinds of transient glitch. You can ignore these hiccups,
2285 because a future fetchmail run will get the mail through.</p>
2287 <p>If the listener tests up, but you have chronic failures trying
2288 to connect to it anyway, your problem is more serious. One way to
2289 work around chronic SMTP connect problems is to use --mda. But this
2290 only attacks the symptom; you may have a DNS or TCP routing
2291 problem. You should really try to figure out what's going on
2292 underneath before it bites you some other way.</p>
2294 <p>We have one report (from toby@eskimo.com) that you can sometimes
2295 solve such problems by doing an <code>smtp</code> declaration with
2296 an IP address that your routing table maps to something other than
2297 the loopback device (he used ppp0).</p>
2299 <p>We also have a report that this error can be caused by having an
2300 /etc/hosts file that associates your client host name with more
2301 than one IP address.</p>
2303 <p>It's also possible that your DNS configuration isn't looking at
2304 <code>/etc/hosts</code> at all. If you're using libc5, look at
2305 <code>/etc/resolv.conf</code>; it should say something like:</p>
2311 <p>so your <code>/etc/hosts</code> file is checked first. If you're
2312 running GNU libc6, check your <code>/etc/nsswitch.conf</code> file.
2313 Make sure it says something like</p>
2319 <p>again, in order to make sure <code>/etc/hosts</code> is seen
2322 <p>If you have a hostname set for your machine, and this hostname
2323 does not appear in /etc/hosts, you will be able to telnet to port
2324 25 and even send a mail with rcpt to: user@host-not-in-/etc/hosts,
2325 but fetchmail can't seem to get in touch with sendmail, no matter
2326 what you set smtpaddress to.</p>
2328 <p>We had another report from a Linux user of fetchmail 2.1 who
2329 solved his SMTP connection problem by removing the reference to
2330 -lresolv from his link line and relinking. Apparently in some older
2331 Linux distributions the libc bind library version works better.</p>
2333 <p>As of 2.2, the configure script has been hacked so the bind
2334 library is linked only if it is actually needed. So under Linux it
2335 won't be, and this particular cause should go away.</p>
2338 <h2><a id="R2" name="R2">R2. When I try to configure an MDA,
2339 fetchmail doesn't work.</a></h2>
2341 <p>(I hear this one from people who have run into the blank-line
2342 problem in <a href="#X1">X1</a>.)</p>
2344 <p>Try sending yourself test mail and retrieving it using the
2345 command-line options '<code>-k -m cat</code>'. This will dump
2346 exactly what fetchmail retrieves to standard output (plus the
2347 Received line fetchmail itself adds to the headers).</p>
2349 <p>If the dump doesn't match what shows up in your mailbox when you
2350 configure an MDA, your MDA is mangling the message. If it doesn't
2351 match what you sent, then fetchmail or something on the server is
2355 <h2><a id="R3" name="R3">R3. Fetchmail dumps core when given an
2356 invalid rc file.</a></h2>
2358 <p>This is usually reported from AIX or Ultrix, but has even been
2359 known to happen on Linuxes without a recent version of
2360 <code>flex</code> installed. The problem appears to be a result of
2361 building with an archaic version of lex.</p>
2363 <p>Workaround: fix the syntax of your .fetchmailrc file.</p>
2365 <p>Fix: build and install the latest version of <a
2366 href="ftp://prep.ai.mit.edu/~ftp/pub/gnu">flex</a> from the Free
2367 Software Foundation. An FSF <a
2368 href="http://www.gnu.ai.mit.edu/order/ftp.html">mirror site</a>
2369 will help you get it faster.</p>
2372 <h2><a id="R4" name="R4">R4. Fetchmail dumps core in -V mode, but
2373 operates normally otherwise.</a></h2>
2375 <p>We've had this reported to us under Linux using libc-5.4.17 and
2376 gcc-2.7.2. It does not occur with libc-5.3.12 or earlier
2379 <p>Workaround: link with GNU malloc rather than the stock C library
2382 <p>We're told there is some problem with the malloc() code in that
2383 version which makes it fragile in the presence of multiple free()
2384 calls on the same pointer (the malloc arena gets corrupted).
2385 Unfortunately it appears from doing gdb traces that whatever free()
2386 calls producing the problem are being made by the C library itself,
2387 not the fetchmail code (they're all from within fclose, and not an
2388 fclose called directly by fetchmail, either).</p>
2391 <h2><a id="R5" name="R5">R5. Running fetchmail in daemon mode
2392 doesn't work.</a><br/>
2395 <p>We have one report from a SunOS 4.1.4 user that trying to run
2396 fetchmail in detached daemon mode doesn't work, but that using the
2397 same options with -N (nodetach) is OK. We have another report of
2398 similar behavior from one Linux user, but many other Linux users
2399 reportt no problem.</p>
2401 <p>If this happens, you have a specific portability problem with
2402 the code in daemon.c that detaches and backgrounds the daemon
2403 fetchmail. The isolated Linux case has been chased down to a
2404 failure in dup(2) that may reflect a glibc bug.</p>
2406 <p>As a workaround, you can start fetchmail with -N and an
2407 ampersand to background it. A Sun user recommends this:</p>
2410 (fetchmail --nodetach <other params> &)
2413 <p>The extra pair of parens is significant --- it makes sure that
2414 the process detaches from the initial shell (one more shell is
2415 started and dies immediately, detaching fetchmail and making it
2416 child of PID 1). This is important when you start fetchmail
2417 interactively and than quit interactive shell. The line above makes
2418 sure fetchmail lives after that!</p>
2421 <h2><a id="R6" name="R6">R6. Fetchmail randomly dies with socket
2424 <p>Check the MTU value in your PPP interface reported by
2425 <code>/sbin/ifconfig</code>. If it's over 600, change it in your
2426 PPP options file. (<code>/etc/ppp/options</code> on my box). Here
2427 are option values that work:</p>
2434 <p>Another circumstance that can trigger this is if you are polling
2435 a virtual-mail-server name that is round-robin connected to
2436 different actual servers, so you get different IP addresses on
2437 different poll cycles. To work around this, change the poll name
2438 either to the real name of one of the servers in the ring or to a
2439 corresponding IP address.</p>
2442 <h2><a id="R7" name="R7">R7. Fetchmail running as root stopped
2443 working after an OS upgrade</a></h2>
2445 <p>In RH 6.0, the HOME value in the boot-time root environment
2446 changed from /root to / as the result of a change in init. Move
2447 your .fetchmailrc or use a -f option to explicitly point at the
2448 file. (Oddly, a similar problem has been reported from Debian
2452 <h2><a id="R8" name="R8">R8. Fetchmail is timing out after fetching
2453 certain messages but before deleting them</a></h2>
2455 <p>There's a TCP/IP stalling problem under Redhat 6.0 (and possibly
2456 other recent Linuxes) that can cause this symptom. Brian Boutel
2460 <p>TCP timestamps are turned on on my Linux boxes (I assume it's
2461 now the default). This uses 12 extra bytes per segment. When the
2462 tcp connection starts, the other end agrees a MSS of 1460, and then
2463 fragments 1460 byte chunks into 1448 and 12, because is is not
2464 allowing for the timestamp.</p>
2466 <p>Then, for reasons I can't explain, it waits a long time
2467 (typically 2 minutes) after the ack is sent before sending the next
2468 (fragmented) packet. Turning off tcp timestamps avoids the
2469 fragmentation and restores normal behaviour. To do this,
2472 <p>echo 0 > /proc/sys/net/ipv4/tcp_timestamps</p>
2474 <p>I'm still unclear about the details of why this is happening. At
2475 least [now] I am now getting good performance and no queue
2480 <h2><a id="R9" name="R9">R9. Fetchmail is timing out during message
2483 <p>This is probably a general networking issue. Sending a "RETR"
2484 command will cause the server to start sending large amounts of
2485 data, which means large packets. If your networking layer has a
2486 packet-fragmentation problem, that's where you'll see it.</p>
2489 <h2><a id="R10" name="R10">R10. Fetchmail is dying with
2492 <p>This probably means you have an <code>mda</code> option. Your
2493 MDA is croaking while being passed a message. Best fix is to remove
2494 the <code>mda</code> option and pass mail to your port 25 SMTP
2497 <p>If for some reason you are invoking sendmail via the
2498 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
2499 don't forget to include the -i switch. Otherwise you will
2500 occasionally get mysterious delivery failures with a SIGPIPE as the
2501 sendmail instance dies. The problem is messages with a single dot
2502 at start of a text line.</p>
2505 <h2><a id="R11" name="R11">R11. My server is hanging or emitting
2506 errors on CAPA.</a></h2>
2508 <p>Your POP3 server is broken. You can work around this with the
2509 declaration <tt>auth password</tt> in your .fetchmailrc.</p>
2512 <h2><a id="R12" name="R12">R12. Fetchmail isn't working and reports
2513 getaddrinfo errors.</a></h2>
2514 <ol><li>Make sure you haven't mistyped the host name or address, and that
2515 your DNS is working. If you cannot fix DNS, give the numeric host
2516 literal, for instance, 192.168.0.1</li>
2517 <li>Make sure your <code>/etc/services</code> file (or other
2518 services database) contains the necessary service entries. If you
2519 cannot fix the services database, use the --port option and give the
2520 numeric port address. Common port addresses
2522 <tr><th>service</th><th>port</th></tr>
2523 <tr><td>IMAP</td><td>143</td></tr>
2524 <tr><td>IMAP+SSL</td><td>993</td></tr>
2525 <tr><td>POP3</td><td>110</td></tr>
2526 <tr><td>POP3+SSL</td><td>995</td></tr>
2529 <h2><a id="H1" name="H1">H1. Fetchmail hangs when used with
2532 <p>Your problem may be with pppd's 'demand' option. We have a
2533 report that fetchmail doesn't play well with it, but works with
2534 pppd if 'demand' is turned off. We have no idea why this is.</p>
2537 <h2><a id="H2" name="H2">H2. Fetchmail hangs during the MAIL FROM
2540 <p>The symptom: 'fetchmail -v' retrieves mail fine, but appears to
2541 hang after sending the MAIL FROM command</p>
2544 SMTP> MAIL FROM: <someone@somewhere>
2547 <p>The hang is actually occuring when sendmail looks up a sender's
2548 address in DNS. The problem isn't in fetchmail but in the
2549 configuration of sendmail. You must enable the 'nodns' and
2550 'nocanonify' features of sendmail.</p>
2552 <p>Here was my fix for RedHat 7.2:</p>
2555 <li># cd /etc/mail</li>
2557 <li># cp sendmail.mc sendmail-mine.mc</li>
2559 <li>Edit sendmail-mine.mc and add lines:
2567 <li>Build a new sendmail.cf
2570 # m4 sendmail-mine.cf > /etc/sendmail.cf
2574 <li>Restart sendmail.</li>
2577 <p>For more details consult the file
2578 /usr/share/sendmail-cf/README.</p>
2581 <h2><a id="H3" name="H3">H3. Fetchmail hangs while fetching
2584 <p>The symption: 'fetchmail -v' retrieves the first few messages,
2585 but hangs returning:</p>
2588 fetchmail: SMTP< 550 5.0.0 Access denied
2589 fetchmail: SMTP> RSET
2590 fetchmail: SMTP< 250 2.0.0 Reset state
2591 .......fetchmail: flushed
2592 fetchmail: POP3> DELE 1
2593 fetchmail: POP3< +OK marked deleted
2596 <p>Check and see if you're allowing sendmail connections through
2599 <p>Adding 'sendmail : 127.0.0.1' to /etc/hosts.allow could solve
2603 <h2><a id="D1" name="D1">D1. I think I've set up fetchmail
2604 correctly, but I'm not getting any mail.</a></h2>
2606 <p>Maybe you have a .forward or alias set up that you've forgotten
2607 about. You should probably remove it.</p>
2609 <p>Or maybe you're trying to run fetchmail in multidrop mode as
2610 root without a .fetchmailrc file. This doesn't do what you think it
2611 should; see question <a href="#C1">C1</a>.</p>
2613 <p>Or you may not be connecting to the SMTP listener. Run fetchmail
2614 -v and see <a href="#R1">R1</a>.</p>
2616 <p>Or you may have your local user set incorrectly. In the
2620 user 'remoteuser' there with password '*' is 'localuser' here
2623 <p>make sure that 'localuser' does exist and can receive mail.</p>
2626 <h2><a id="D2" name="D2">D2. All my mail seems to disappear after a
2627 dropped connection.</a></h2>
2629 <p>One POP3 daemon used in the Berkeley Unix world that reports
2630 itself as POP3 version 1.004 actually throws the queue away. 1.005
2631 fixed that. If you're running this one, upgrade immediately. (It
2632 also truncates long lines at column 1024)</p>
2634 <p>Many POP servers, if an interruption occurs, will restore the
2635 whole mail queue after about 10 minutes. Others will restore it
2636 right away. If you have an interruption and don't see it right
2637 away, cross your fingers and wait ten minutes before retrying.</p>
2639 <p>Some servers (such as Microsoft's NTMail) are mis-designed to
2640 restore the entire queue, including messages you have deleted. If
2641 you have one of these and it flakes out on you a lot, try setting a
2642 small <code>--fetchlimit</code> value. This will result in more IP
2643 connects to the server, but will mean it actually executes changes
2644 to the queue more often.</p>
2646 <p>Qualcomm's qpopper, used at many BSD Unix sites, is better
2647 behaved. If its connection is dropped, it will first execute all
2648 DELE commands as though you had issued a QUIT (this is a technical
2649 violation of the POP3 RFCs, but a good idea in a world of flaky
2650 phone lines). Then it will re-queue any message that was being
2651 downloaded at hangup time. Still, qpopper may require a noticeable
2652 amount of time to do deletions and clean up its queue. (Fetchmail
2653 waits a bit before retrying in order to avoid a 'lock busy'
2657 <h2><a id="D3" name="D3">D3. Mail that was being fetched when I
2658 interrupted my fetchmail seems to have been vanished.</a></h2>
2660 <p>Fetchmail only sends a delete mail request to the server when
2661 either (a) it gets a positive delivery acknowledgment from the SMTP
2662 listener, or (b) it gets one of the spam-filter errors (see the
2663 description of the <code>antispam></code> option) from the
2664 listener. No interrupt can cause it to lose mail.</p>
2666 <p>However, IMAP2bis has a design problem in that its normal fetch
2667 command marks a message 'seen' as soon as the fetch command to get
2668 it is sent down. If for some reason the message isn't actually
2669 delivered (you take a line hit during the download, or your port 25
2670 listener can't find enough free disk space, or you interrupt the
2671 delivery in mid-message) that 'seen' message can lurk invisibly in
2672 your server mailbox forever.</p>
2674 <p>Workaround: add the '<code>fetchall</code>' keyword to your
2677 <p>Solution: switch to an <a href="http://www.imap.org">IMAP4</a>
2681 <h2><a id="M1" name="M1">M1. I've declared local names, but all my
2682 multidrop mail is going to root anyway.</a></h2>
2684 <p>Somehow your fetchmail is never recognizing the hostname part of
2685 recipient names it parses out of To/Cc/envelope-header lines as
2686 matching the name of the mailserver machine. To check this, run
2687 fetchmail in foreground with -v -v on. You will probably see a lot
2688 of messages with the format "line rejected, %s is not an alias of
2689 the mailserver" or "no address matches; forwarding to %s."</p>
2691 <p>These errors usually indicate some kind of DNS configuration
2692 problem either on the server or your client machine.</p>
2694 <p>The easiest workaround is to add a '<code>via</code>' option (if
2695 necessary) and add enough aka declarations to cover all of your
2696 mailserver's aliases, then say '<code>no dns</code>'. This will
2697 take DNS out of the picture (though it means mail may be
2698 uncollected if it's sent to an alias of the mailserver that you
2699 don't have listed).</p>
2701 <p>It would be better to fix your DNS, however. DNS problems can
2702 hurt you in lots of ways, for example by making your machines
2703 intermittently or permanently unreachable to the rest of the
2706 <p>Occasionally these errors indicate the sort of header-parsing
2707 problem described in <a href="#M7">M7</a>.</p>
2710 <h2><a id="M2" name="M2">M2. I can't seem to get fetchmail to route
2711 to a local domain properly.</a></h2>
2713 <p>A lot of people want to use fetchmail as a poor man's
2714 internetwork mail gateway, picking up mail accumulated for a whole
2715 domain in a single server mailbox and then routing based on what's
2716 in the To/Cc/Bcc lines.</p>
2718 <p>In general, this is not really a good idea. It would be smarter
2719 to just let the mail sit in the mailserver's queue and use
2720 fetchmail's ETRN or ODMR modes to trigger SMTP sends periodically
2721 (of course, this means you have to poll more frequently than the
2722 mailserver's expiration period). If you can't arrange this, try
2723 setting up a UUCP feed.</p>
2725 <p>If neither of these alternatives is available, multidrop mode
2726 may do (though you <em>are</em> going to get hurt by some mailing
2727 list software; see the caveats under THE USE AND ABUSE OF MULTIDROP
2728 MAILBOXES on the man page). If you want to try it, the way to do it
2729 is with the '<code>localdomains</code>' option.</p>
2731 <p>In general, if you use localdomains you need to make sure of two
2734 <p><strong>1. You've actually set up your .fetchmailrc entry to
2735 invoke multidrop mode.</strong></p>
2737 <p>Many people set a '<code>localdomains</code>' list and then
2738 forget that fetchmail wants to see more than one name (or the
2739 wildcard '*') in a '<code>here</code>' list before it will do
2740 multidrop routing.</p>
2742 <p><strong>2. You may have to set 'no envelope'.</strong></p>
2744 <p>Normally, multidrop mode tries to deduce an envelope address
2745 from a message before parsing the To/Cc/Bcc lines (this enables it
2746 to avoid losing to mailing list software that doesn't put a
2747 recipient address in the To lines).</p>
2749 <p>Some ways of accumulating a whole domain's messages in a single
2750 server mailbox mean it all ends up with a single envelope address
2751 that is useless for rerouting purposes. You may have to set
2752 '<code>no envelope</code>' to prevent fetchmail from being
2753 bamboozled by this.</p>
2755 <p>Check also answer <a href="#T1">T1</a> on a reliable way to do
2756 multidrop delivery if your ISP (or your mail redirection provider)
2760 <h2><a id="M3" name="M3">M3. I tried to run a mailing list using
2761 multidrop, and I have a mail loop!</a></h2>
2763 <p>This isn't fetchmail's fault. Check your mailing list. If the
2764 list expansion includes yourself or anybody else at your mailserver
2765 (that is, not on the client side) you've created a mail loop. Just
2766 chop the host part off any local addresses in the list.</p>
2768 <p>If you use sendmail, you can check the list expansion with
2769 <code>sendmail -bv</code>.</p>
2772 <h2><a id="M4" name="M4">M4. My multidrop fetchmail seems to be
2773 having DNS problems.</a></h2>
2775 <p>We have one report from a Linux user (not the same one as in <a
2776 href="#R1">R1</a>!) who solved this problem by removing the
2777 reference to -lresolv from his link line and relinking. Apparently
2778 in some older Linux distributions the libc5 bind library version
2781 <p>As of 2.2, the configure script has been hacked so the bind
2782 library is linked only if it is actually needed. So under Linux it
2783 won't be, and this problem should go away.</p>
2786 <h2><a id="M5" name="M5">M5. I'm seeing long DNS delays before each
2787 message is processed.</a></h2>
2789 <p>Use the '<code>aka</code>' option to pre-declare as many of your
2790 mailserver's DNS names as you can. When an address's host part
2791 matches an aka name, no DNS lookup needs to be done to check
2794 <p>If you're sure you've pre-declared all of your mailserver's DNS
2795 names, you can use the '<code>no dns</code>' option to prevent
2796 other hostname parts from being looked up at all.</p>
2798 <p>Sometimes delays are unavoidable. Some SMTP listeners try to
2799 call DNS on the From-address hostname as a way of checking that the
2800 address is valid.</p>
2803 <h2><a id="M6" name="M6">M6. How do I get multidrop mode to work
2804 with majordomo?</a></h2>
2806 <p>In order for sendmail to execute the command strings in the
2807 majordomo alias file, it is necessary for sendmail to think that
2808 the mail it receives via SMTP really is destined for a local user
2809 name. A normal virtual-domain setup results in delivery to the
2810 default mailbox, rather than expansion through majordomo.</p>
2812 <p>Michael <michael@bizsystems.com> gave us a recipe for
2813 dealing with this case that pairs a run control file like this:</p>
2816 poll your.pop3.server proto pop3:
2818 localdomains virtual.localdomain1.com virtual.localdomain2.com ...
2819 user yourISPusername is root * here,
2820 password yourISPpassword fetchall
2823 <p>with a hack on your local sendmail.cf like this:</p>
2826 #############################################
2827 # virtual info, local hack for ruleset 98 #
2828 #############################################
2830 # domains to treat as direct mapped local domain
2832 CVvirtual.localdomain1.com virtual.localdomain2.com ...
2833 ---------------------------
2835 -------------------------
2836 # handle virtual users
2838 R$+ <@ $=V . > $: $1 < @ $j . >
2839 R< @ > $+ < @ $=V . > $: $1 < @ $j . >
2840 R< @ > $+ $: $1
2841 R< error : $- $+ > $* $#error $@ $1 $: $2
2842 R< $+ > $+ < @ $+ > $: $>97 $1
2845 <p>This ruleset just strips virtual domain names off the addresses
2846 of incoming mail. Your sendmail must be 8.8 or newer for this to
2847 work. Michael says:</p>
2849 <blockquote>I use this scheme with 2 virtual domains and the
2850 default ISP user+domain and service about 30 mail accounts +
2851 majordomo on my inside pop3 server with fetchmail and sendmail
2855 <h2><a id="M7" name="M7">M7. Multidrop mode isn't parsing envelope
2856 addresses from my Received headers as it should.</a></h2>
2858 <p>It may happen that you're getting what appear to be well-formed
2859 sendmail Received headers, but fetchmail can't seem to extract an
2860 envelope address from them. There can be a couple of reasons for
2863 <h3>Spurious Received lines need to be skipped:</h3>
2865 <p>First, fetchmail might be looking at the wrong Received header.
2866 Normally it looks only on the first one it sees, on the theory that
2867 that one was last added and is going to be the one containing your
2868 mailserver's theory of who the message was addressed to.</p>
2870 <p>Some (unusual) mailserver configurations will generate extra
2871 Received lines which you need to skip. To arrange this, use the
2872 optional skip prefix argument of the 'envelope' option; you may
2873 need to say something like '<code>envelope 1 Received</code>' or
2874 '<code>envelope 2 Received</code>'.</p>
2876 <h3>The 'by' clause doesn't contain a mailserver alias:</h3>
2878 <p>When fetchmail parses a Received line that looks like</p>
2881 Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
2882 by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
2883 for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
2886 <p>it checks to see if 'iserv.ttns.net' is a DNS alias of your
2887 mailserver before accepting 'ksturgeon@fbceg.org' as an envelope
2888 address. This check might fail if your DNS were misconfigured, or
2889 if you were using 'no dns' and had failed to declare iserv.ttns.net
2890 as an alias of your server.</p>
2893 <h2><a id="M8" name="M8">M8. Users are getting multiple copies of
2896 <p>It's a consequence of multidrop. What's happening is that you
2897 have N users subscribed to the same list. The list software sends N
2898 copies, not knowing they will end up in the same multidrop box.
2899 Since they are both locally addressed to all N users, fetchmail
2900 delivers N copies to each user.</p>
2902 <p>Fetchmail tries to eliminate adjacent duplicate messages in a
2903 multidrop mailbox. However, this logic depends on the message-ID
2904 being identical in both copies. It also depends on the two copies
2905 being adjacent in the server mailbox. The former is usually the
2906 case, but the latter condition sometimes fails in a
2907 timing-dependent way if the server was processing multiple incoming
2910 <p>I could eliminate this problem by keeping a list of all
2911 message-IDs received during a poll so far and dropping any message
2912 that matches a seen mail ID. The trouble is that this is an O(N**2)
2913 operation that might significantly slow down the retrieval of large
2917 <h2><a id="X1" name="X1">X1. Spurious blank lines are appearing in
2918 the headers of fetched mail.</a></h2>
2920 <p>What's probably happening is that the POP/IMAP daemon on your
2921 mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
2922 something in your delivery path (most likely an old version of the
2923 <em>deliver</em> program, which sendmail often calls to do local
2924 delivery) is failing to recognize it as a header.</p>
2926 <p>This is not fetchmail's problem. The first thing to try is
2927 installing a current version of <em>deliver</em>. If this doesn't
2928 work, try to figure out which other program in your mail path is
2929 inserting the blank line and replace that. If you can't do either
2930 of these things, pick a different MDA (such as procmail) and
2931 declare it with the '<code>mda</code>' option.</p>
2934 <h2><a id="X2" name="X2">X2. My mail client can't see a Subject
2937 <p>First, see <a href="#X1">X1</a>. This is quite probably the same
2938 problem (X-POP3-Rcpt header or something similar being inserted by
2939 the server and choked on by an old version of
2940 <em>deliver</em>).</p>
2942 <p>The O'Reilly sendmail book does warn that IDA sendmail doesn't
2943 process X- headers correctly. If this is your problem, all I can
2944 suggest is replacing IDA sendmail, because it's broken and not
2945 RFC822 conformant.</p>
2948 <h2><a id="X3" name="X3">X3. Messages containing "From" at start of
2949 line are being split.</a></h2>
2951 <p>If you know the messages aren't split in your server mailbox,
2952 then this is a problem with your POP/IMAP server, your client-side
2953 SMTP listener or your local delivery agent. Fetchmail cannot split
2956 <p>Some POP server daemons ignore Content-Length headers and split
2957 messages on From lines. We have one report that the 2.1 version of
2958 the BSD popper program (as distributed on Solaris 2.5 and
2959 elsewhere) is broken this way.</p>
2961 <p>You can test this. Declare an mda of 'cat' and send yourself one
2962 piece of mail containing "From" at start of a line. If you see a
2963 split message, your POP/IMAP server is at fault. Upgrade to a more
2966 <p>Sendmail and other SMTP listeners don't split RFC822 messages
2967 either. What's probably happening is either sendmail's local
2968 delivery agent or your mail reader are not quite RFC822-conformant
2969 and are breaking messages on what it thinks are Unix-style From
2970 headers. You can figure out which by looking at your client-side
2971 mailbox with vi or more. If the message is already split in your
2972 mailbox, your local delivery agent is the problem. If it's not,
2973 your mailreader is the problem.</p>
2975 <p>If you can't replace the offending program, take a look at your
2976 sendmail.cf file. There will likely be a line something like</p>
2979 Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
2982 <p>describing your local delivery agent. Try inserting the 'E'
2983 option in the flags part (the F= string). This will make sendmail
2984 turn each dangerous start-of-line From into a >From, preventing
2985 programs further downstream from acting up.</p>
2988 <h2><a id="X4" name="X4">X4.</a> <a id="generic_mangling"
2989 name="generic_mangling">My mail is being mangled in a new and
2990 different way</a></h2>
2992 <p>The first thing you need to do is pin down what program is doing
2993 the mangling. We don't like getting bug reports about fetchmail
2994 that are actually due to some other program's malfeasance, so
2995 please go through this diagnostic sequence before sending us a
2998 <p>There are five possible culprits to consider, listed here in the
2999 order they pass your mail:</p>
3002 <li>Programs upstream of your server mailbox.</li>
3004 <li>The POP or IMAP server on your mailserver host.</li>
3006 <li>The fetchmail program itself.</li>
3008 <li>Your local sendmail.</li>
3010 <li>Your LDA (local delivery agent), as called by sendmail or
3011 specified by <code>mda</code>.</li>
3014 <p>Often it happens that fetchmail itself is OK, but using it
3015 exposes pre-existing bugs in your downstream software, or your
3016 downstream software has a bad interaction with POP/IMAP. You need
3017 to pin down exactly where the message is being garbled in order to
3018 deduce what is actually going on.</p>
3020 <p>The first thing to do is send yourself a test message, and
3021 retrieve it with a .fetchmailrc entry containing the following (or
3022 by running with the equivalent command-line options):</p>
3025 mda "cat >MBOX" keep fetchall
3028 <p>This will capture what fetchmail gets from the server, except
3029 for (a) the extra Received header line fetchmail prepends, (b)
3030 header address changes due to <code>rewrite</code>, and (c) any
3031 end-of-line changes due to the <code>forcecr</code> and
3032 <code>stripcr</code> options. MBOX will in fact contain what
3033 programs downstream of fetchmail see.</p>
3035 <p>The most common causes of mangling are bugs and
3036 misconfigurations in those downstream programs. If MBOX looks
3037 unmangled, you will know that is what is going on and that it is
3038 not fetchmail's problem. Take a look at the other FAQ items in this
3039 section for possible clues about how to fix your problem.</p>
3041 <p>If MBOX looks mangled, the next thing to do is compare it with
3042 your actual server mailbox (if possible). That's why you specified
3043 <code>keep</code>, so the server copy would not be deleted. If your
3044 server mailbox looks mangled, programs upstream of your server
3045 mailbox are at fault. Unfortunately there is probably little you
3046 can do about this aside from complaining to your site postmaster,
3047 and nothing at all fetchmail can do about it!</p>
3049 <p>More likely you'll find that the server copy looks OK. In that
3050 case either the POP/IMAP server or fetchmail is doing the mangling.
3051 To determine which, you'll need to telnet to the server port and
3052 simulate a fetchmail session yourself. This is not actually hard
3053 (both POP3 and IMAP are simple, text-only, line-oriented protocols)
3054 but requires some attention to detail. You should be able to use a
3055 fetchmail -v log as a model for a session, but remember that the
3056 "*" in your LOGIN or PASS command dump has to be replaced with your
3057 actual password.</p>
3059 <p>The objective of manually simulating fetchmail is so you can see
3060 exactly what fetchmail sees. If you see a mangled message, then
3061 your server is at fault, and you probably need to complain to your
3062 mailserver administrators. However, we like to know what the broken
3063 servers are so we can warn people away from them. So please send us
3064 a transcript of the session including the mangling <em>and the
3065 server's initial greeting line</em>. Please tell us anything else
3066 you think might be useful about the server, like the server host's
3067 operating system.</p>
3069 <p>If your manual fetchmail simulation shows an unmangled message,
3070 congratulations. You've found an actual fetchmail bug, which is a
3071 pretty rare thing these days. Complain to us and we'll fix it.
3072 Please include the session transcript of your manual fetchmail
3073 simulation along with the other things described in the FAQ entry
3074 on <a href="#G3">reporting bugs</a>.</p>
3077 <h2><a id="X5" name="X5">X5. Using POP3, retrievals seems to be
3078 fetching too much!</a></h2>
3080 <p>This may happen in versions of fetchmail after 4.4.1 and before
3081 4.4.8. Versions after 4.4.1 use POP3's TOP command rather than
3082 RETR, in order to avoid marking the message seen (leaving it unseen
3083 is helpful for later recovery if you lose your connection in the
3084 middle of a retrieval).</p>
3086 <p>Versions of fetchmail from 4.4.2 through 4.4.7 had a bad
3087 interaction with Eudora qpopper versions 2.3 and later. The TOP
3088 bounds check was fooled by an overflow condition in the TOP
3089 argument. Decrementing the TOP argument in 4.4.7 fixed this.</p>
3091 <p>Fix: Upgrade to a later version of fetchmail.</p>
3093 <p>Workaround: set the <code>fetchall</code> option. Under POP3
3094 this has the side effect of forcing RETR use.</p>
3097 <h2><a id="X6" name="X6">X6. My mail attachments are being dropped
3098 or mangled.</a></h2>
3100 <p>Fetchmail doesn't discard attachments; fetchmail doesn't have any idea
3101 that attachments are there. Fetchmail treats the body of each message as
3102 an uninterpreted byte stream and passes it through without alteration.
3103 If you are not receiving attachments through fetchmail, it is because
3104 your mailserver is not sending them to you.</p>
3106 <p>The fix for this is to replace your mailserver with one that works.
3107 If its operating system makes this difficult, you should replace its
3108 operating system with one that works. Windows- and NT-based POP servers
3109 seem especially prone to mangle attachments. If you are running one
3110 of these, replacing your server with a Unix machine is probably the
3111 only effective solution.</p>
3113 <p>We've had sporadic reports of problems with Microsoft Exchange and
3114 Outlook servers. These sometimes randomly fail to ship
3115 attachments to your client. This is a known bug, acknowledged by
3118 <p>They may also mangle the attachments they do pass through. If you
3119 see unreadable attachments with a ContentType of "application/x-tnef",
3120 you're having this problem. The <a
3121 href="http://world.std.com/~damned/software.html">TNEF</a> utility may
3124 <p>The Mail Max POP3 server and the InterChange and Imail IMAP
3125 servers are known to simply drop MIME attachments when uploading
3128 <p>We've also had a report that Lotus Notes sometimes trashes the
3129 MIME type of messages. In particular, it seems to modify MIME
3130 headers of type application/pdf, mangling the type to
3131 application/octet-stream. It may corrupt other MIME types as
3134 <p>The IMAP service of Lotus Domino has a known bug in the way it
3135 generates MIME Content-type headers (observed on Lotus Domino
3136 5.0.2b). It's a subtle one that doesn't show up when Netscape
3137 Messenger and other clients use a FETCH BODY[] to grab the whole
3138 message. When fetchmail uses FETCH RFC822.HEADER and FETCH
3139 RFC822.TEXT to get first the header and then the body, Domino
3140 generates different Boundary tags for each part, .e.g. one tag is
3141 declared in the Content-type header and another is used to separate
3142 the MIME parts in the body. This doesn't work. (I have heard a
3143 rumor that this bug is scheduled to be fixed in Domino release 6;
3144 you can find a workaround at contrib/domino.)</p>
3146 <p>Rob Funk explains: Unfortunately there also remain many mail
3147 user agents that don't write correct MIME messages. One big
3148 offender is Sun MailTool attachments, which are formatted enough
3149 like MIME that some programs could get confused; these are
3150 generated by the mailtool and dtmail programs (the mail programs in
3151 Sun's OpenWindows and CDE environments).</p>
3153 <p>One solution to problems related to misformatted MIME
3154 attachments is the <a
3155 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/">emil</a>
3157 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/TUTORIAL.html">tutorial</a>
3158 file at that site for details on emil. It is useful for converting
3159 character sets, attachment encodings, and attachment formats. At
3160 this writing, emil does not appear to have been maintained since a
3161 patch to version 2.1.0beta9 in late 1997, but it is still
3164 <p>One good way of using emil is from within procmail. You can have
3165 procmail look for signs of problematic message formatting, and pipe
3166 those messages through emil to be fixed. emil will not always be
3167 able to fix the problem, in which case the message is
3170 <p>A possible rule to be inserted into a .procmailrc file for using
3175 * 1^1 ^Content-Type: \/X-sun[^;]*
3176 * 1^1 ^Content-Type: \/application/mac-binhex[^;]*
3177 * 1^1 ^Content-Transfer-Encoding: \/x-binhex[^;]*
3178 * 1^1 ^Content-Transfer-Encoding: \/x-uuencode[^;]*
3180 LOG="Converting $MATCH
3183 | emil -A B -T Q -B BA -C iso-8859-1 -H Q -F MIME \
3184 | gawk '{gsub(/\r\n?/,"\n");print $0}'
3188 <p>The "1^1" in the conditions is a way of specifying to procmail
3189 that if any one of the four listed expressions is found in the
3190 message, the total condition is considered true, and the message
3191 gets passed into emil. These four subconditions check whether the
3192 message has a Sun attachment, a binhex attachment, or a uuencoded
3193 attachment; there are others that could be added to check these
3194 things better and to check other relevant conditions. The "LOG="
3195 line writes a line into the procmail log; the lone double-quote
3196 beginning the following line makes sure the log entry gets an
3197 end-of-line character. The call to gawk (GNU awk) is for fixing
3198 end-of-line conventions, since emil sometimes leaves those in the
3199 format of the originating machine; it could probably be replaced
3200 with a sed subsitution.</p>
3202 <p>The emil call itself tries to ensure that the message uses:</p>
3205 <li>BinHex encoding for any Apple Macintosh-only attachments</li>
3207 <li>Quoted-Printable encoding for text (when necessary)</li>
3209 <li>Base64 Encoding for binary attachments</li>
3211 <li>iso-8859-1 character set for text (unfortunately emil can't yet
3212 convert from windows-1252 to iso-8859-1)</li>
3214 <li>Quoted-Printable encoding for headers</li>
3216 <li>MIME attachment format</li>
3219 <p>Most of these (the primary exceptions being the character set
3220 and the Apple binary format) are as they should be for good
3221 internet interoperability.</p>
3223 <p>Some mail servers (Lotus Domino is a suspect here) mangle
3224 Sun-formatted messages, so the conversion to MIME needs to happen
3225 before such programs see the message. The ideal is to rid the world
3226 of Sun-formatted messages: don't use mailtool for sending
3227 attachments (it doesn't understand MIME anyway, and most of the
3228 world doesn't understand its attachments, so it really shouldn't be
3229 used at all), and make sure dtmail is set to use MIME rather than
3230 mailtool's format.</p>
3233 <h2><a id="X7" name="X7">X7. Some mail attachments are hanging
3236 <p>This isn't fetchmail's problem either; fetchmail doesn't know
3237 anything about mail attachments and doesn't treat them any
3238 differently from plain message data.</p>
3240 <p>The most usual cause of this problem seems to be bugs in your
3241 network transport layer's capability to handle the very large
3242 TCP/IP packets that attachments tend to turn into. You can test
3243 this theory by trying to download the offending message through a
3244 webmail account; using HTTP for the message tends to simulate
3245 large-packet stress rather well, and you will probably find that
3246 the messages that seem to be choking fetchmail will make your HTTP
3247 download speed drop to zero.</p>
3249 <p>This problem can be caused by subtle bugs in the
3250 packet-reassembly layer of your TCP/IP stack; these often don't
3251 manifest at normal packet sizes. It may also be caused by
3252 malfunctioning path-MTU discovery on the mailserver. Or, if there's
3253 a modem in the link, it may be because the attachment contains the
3254 Hayes mode escape "+++".</p>
3257 <h2><a id="X8" name="X8">X8. A spurious ) is being appended to my
3260 <p>Blame it on that rancid pile of dung and offal called Microsoft
3261 Exchange. Due to the problem described in <a href="#S2">S2</a>, the
3262 IMAP support in fetchmail cannot follow the IMAP protocol 100%.
3263 Most of the time it doesn't matter, but if you combine it with an
3264 SMTP server that behaves unusually, you'll get a spurious ) at
3267 <p>One piece of software that can trigger this is the Interchange
3268 mail server, as used by, e.g., mailandnews.com. Here's what
3271 <p>1. Someone sends mail to your account. The last line of the
3272 message contains text. So at the SMTP level, the message ends with,
3273 e.g. "blahblah\r\n.\r\n"</p>
3275 <p>2. The SMTP handler sees the final "\r\n.\r\n" and recognizes
3276 the end of the message. However, instead of doing the normal thing,
3277 which is tossing out the ".\r\n" and leaving the first '\r\n' as
3278 part of the email body, Interchange throws out the whole
3279 "\r\n.\r\n", and leaves the email body without any line terminator
3280 at the end of it. RFC821 does not forbid this, though it probably
3283 <p>3. Fetchmail, or some other IMAP client, asks for the message.
3284 IMAP returns it, but it's enclosed inside parentheses, according to
3285 the protocol. The message size in bytes is also present. Because
3286 the message doesn't end with a line terminator, the IMAP client
3294 <p>where the ')' is from IMAP.</p>
3296 <p>4. Fetchmail only deals with complete lines, and can't trust the
3297 stated message size because Microsoft Exchange fscks it up.</p>
3299 <p>5. As a result, fetchmail takes the final 'blahblah)' and puts
3300 it at the end of the message it forwards on. If you have verbosity
3301 on, you'll get a message about actual != expected.</p>
3303 <p>There is no fix for this. The nuke mentioned in <a
3304 href="#S2">S2</a> looks more tempting all the time.</p>
3307 <h2><a id="O1" name="O1">O1. The --logfile option doesn't work if
3308 the logfile doesn't exist.</a></h2>
3310 <p>This is a feature, not a bug. It's in line with normal practice
3311 for system daemons and allows you to suppress logging by removing
3312 the log, without hacking potentially fragile startup scripts. To
3313 get around it, just touch(1) the logfile before you run fetchmail
3314 (this will have no effect on the contents of the logfile if it
3315 already exists).</p>
3318 <h2><a id="O2" name="O2">O2. Every time I get a POP or IMAP message
3319 the header is dumped to all my terminal sessions.</a></h2>
3321 <p>Fetchmail uses the local sendmail to perform final delivery,
3322 which Netscape and other clients doesn't do; the announcement of
3323 new messages is done by a daemon that sendmail pokes. There should
3324 be a "biff" command to control this. Type</p>
3330 <p>to turn it off. If this doesn't work, try the command</p>
3336 <p>which is essentially what <code>biff -n</code> will do. If this
3337 doesn't work, comment out any reference to "comsat" in your
3338 /etc/inetd.conf file and restart inetd.</p>
3340 <p>In Slackware Linux distributions, the last line in /etc/profile
3353 to solve the problem system-wide.
3356 <h2><a id="O3" name="O3">O3. Does fetchmail reread its rc file
3357 every poll cycle?</a></h2>
3359 <p>No, but versions 5.2.2 and later will notice when you modify
3360 your rc file and restart, reading it.</p>
3363 <h2><a id="O4" name="O4">O4. Why do deleted messages show up again
3364 when I take a line hit while downloading?</a></h2>
3366 <p>Because you're using a POP3 other than Qualcomm qpopper, or an
3367 IMAP with a long expunge interval.</p>
3369 <p>According to the POP3 RFCs, deletes aren't actually performed
3370 until you issue the end-of-session QUIT command. Fetchmail cannot
3371 fix this, because doing it right takes cooperation from the server.
3372 There are two possible remedies:</p>
3374 <p>One is to switch to qpopper (the free POP3 server from Qualcomm,
3375 the Eudora people). The qpopper software violates the POP3 RFCs by
3376 doing an expunge (removing deleted messages) on a line hangup, as
3377 well as on processing a QUIT command.</p>
3379 <p>The other (which we recommend) is to switch to <a
3380 href="http://www.imap.org">IMAP</a>. IMAP has an explicit expunge
3381 command and fetchmail normally uses it to delete messages
3382 immediately after they are downloaded.</p>
3384 <p>If you get very unlucky, you might take a line hit in the window
3385 between the delete and the expunge. If you've set a longer expunge
3386 interval, the window gets wider. This problem should correct itself
3387 the next time you complete a successful query.</p>
3390 <h2><a id="O5" name="O5">O5. Why is fetched mail being logged with
3391 my name, not the real From address?</a></h2>
3393 <p>Because logging is done based on the address indicated by the
3394 sending SMTP's MAIL FROM, and some listeners are picky about that
3397 <p>Some SMTP listeners get upset if you try to hand them a MAIL
3398 FROM address naming a different host than the originating site for
3399 your connection. This is a feature, not a bug -- it's supposed to
3400 help prevent people from forging mail with a bogus origin site.
3401 (RFC 1123 says you shouldn't do this exclusion...)</p>
3403 <p>Since the originating site of a fetchmail delivery connection is
3404 localhost, this effectively means these picky listeners will barf
3405 on any MAIL FROM address fetchmail hands them with an @ in it!</p>
3407 <p>Versions 2.1 and up try the header From address first and fall
3408 back to the calling-user ID. So if your SMTP listener isn't picky,
3409 the log will look right.</p>
3412 <h2><a id="O6" name="O6">O6. I'm seeing long sendmail delays or
3413 hangs near the start of each poll cycle.</a></h2>
3415 <p>Sendmail does a hostname lookup when it first starts up, and
3416 also each time it gets a HELO in listener mode.</p>
3418 <p>Your resolver configuration may be causing one of these lookups
3419 to fail and time out. Check <code>/etc/resolv.conf</code> and
3420 <code>/etc/hosts</code> file. Make sure your hostname and
3421 fully-qualified domain name are both in <code>/etc/hosts</code>,
3422 and that hosts is looked at before DNS is queried. You probably
3423 also want your remote mail server(s) to be in the hosts file.</p>
3425 <p>You can suppress the startup-time lookup if need to by
3426 reconfiguring with <code>FEATURE(nodns)</code>.</p>
3428 <p>Configuring your bind library to cache DNS lookups locally may
3429 help, and is a good idea for speeding up other services as well.
3430 Switching to a faster MTA like qmail or exim might help.</p>
3433 <h2><a id="O7" name="O7">O7. Why doesn't fetchmail deliver mail in
3434 date-sorted order?</a></h2>
3436 <p>Because that's not the order the server hands it to fetchmail
3439 <p>Fetchmail getting mail from a POP server delivers mail in the
3440 order that your server delivers mail. Fetchmail can't do anything
3441 about this; it's a limitation of the underlying POP protocol.</p>
3443 <p>In theory it might be possible for fetchmail in IMAP mode to
3444 sort messages by date, but this would be in violation of two basics
3445 of fetchmail's design philosophy: (a) to be as simple and
3446 transparent a pipe as possible, and (b) to <em>hide</em>, rather
3447 than emphasize, the differences between the remote-fetch protocols
3450 <p>Re-ordering messages is a user-agent function, anyway.</p>
3453 <h2><a id="O8" name="O8">O8. I'm using pppd. Why isn't my monitor
3454 option working?</a></h2>
3456 <p>There is a combination of circumstances that can confuse
3457 fetchmail. If you have set up demand dialing with pppd, and pppd
3458 has an idle timeout, and you have lcp-echo-interval set, then the
3459 lcp-echo-interval time must be longer than the pppd idle timeout.
3460 Otherwise it is going keep increasing the packet counters that
3461 fetchmail relies upon, triggering fetchmail into polling after its
3462 own delay interval and thus preventing the pppd link from ever
3463 reaching its inactivity timeout.</p>
3466 <h2><a id="O9" name="O9">O9. Why does fetchmail keep retrieving the
3467 same messages over and over?</a></h2>
3469 <p>First, check to see that you haven't enabled the
3470 <cite>keep</cite> and <cite>fetchall</cite> option. If you have,
3471 turn <cite>keep</cite> off.</p>
3473 <p>There are various forms of lossage involving the POP3 UIDL
3474 feature that can lead to all your old messages being seen again
3475 after a line drop. I have given up trying to fix these, as the UIDL
3476 code breaks worse every time I touch it. The problem is
3477 fundamental; maintaining and garbage-collecting the right kind of
3478 client-side state is just hard. Whoever put UIDLs in RFC1725 and
3479 removed LAST should be hung up by his thumbs and whipped with
3480 scorpions. The right answers are either (a) live with the
3481 occasional breakage, (b) switch to IMAP4, or (c) fix the code
3482 yourself and send me a patch. Unless you choose (c), I don't want
3483 to hear about it.</p>
3485 <p>This can also happen when some other mail client is logged in to
3486 your mail server, if it uses a simple exclusive-locking scheme (and
3487 many, especially most POP3 servers, do exactly that). Your
3488 fetchmail is able to retrieve the messages, but because the mailbox
3489 is write-locked by the other instance yours can neither mark
3490 messages seen or delete them. The solution is to either (a) wait
3491 for the other client to finish, or (b) terminate it.</p>
3493 <p>James Stevens <James.Stevens at kyzo.com> writes:</p>
3495 <p><em>We had a Linux box dialing the Net and collecting mail from
3496 an NT POP3 server. Fetchmail was correctly collecting and deleting
3497 each e-mail one by one. However,the dial-up connection was very
3498 unreliable and would often just drop out in the middle of a
3501 <p><em>Interestingly, unless the TCP POP3 connection was terminated
3502 normally (I guess with a POP3 "QUIT" command) NT would then roll
3503 back all the deletes !!!</em></p>
3505 <p><em>This meant if the first e-mail was very large it might just
3506 end up continuously collecting it, basically jamming the queue. Or,
3507 if the queue became very full itmight never get a long enough phone
3508 connection to retrieve the entire mailbox, and NT would roll back
3509 any deletes, so it would end up collecting (and delivering) the
3510 first few e-mails again and again. As the POP3 mailbox became
3511 fuller and fuller the chances of getting a connection long enough
3512 to collect theentire mailbox became smaller and smaller.</em></p>
3514 <p><em>Our solution was to make fetchmail only collect a few (say 5
3515 or 10) e-mails at atime, thus trying to ensure that the POP3
3516 connection is terminated correctly.</em></p>
3518 <p>Unfortunately, this is exactly the way POP3 servers are supposed
3519 to behave on a line drop, according to the RFCs. I recommend
3520 switching to IMAP and using a short expunge interval.</p>
3523 <h2><a id="O10" name="O10">O10. Why is the received date on all my
3524 messages the same?</a></h2>
3526 <p>This is a design choice in your MTA, not fetchmail. It's taking
3527 the received date from the last Received header.</p>
3530 <h2><a name="O11">O11. I keep getting messages that say "Repoll
3531 immediately" in my logs.</a></h2>
3533 <p>This is your server barfing on the CAPA probe that fetchmail sends.</p>
3535 <p>If you run fetchmail in daemon mode (say "set daemon 600"), you will
3536 get the message only once per run.</p>
3538 <p>If you set an authentication method explicitly (say, with
3539 <code>auth password</code>), you will never get the message.</p>
3542 <h2><a name="O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a></h2>
3544 <p>This is a feature, not a bug.</p>
3546 <p>Any 4xx response (like 451) indicates a transient (temporary) error.
3547 This means that the mail could be accepted if retried later. Lookup
3548 failures are normally transient errors as a mail should not get
3549 rejected if a dns server is unreachable or down.</p>
3551 <p>A permanent reject response is of the form 5xx (like 550).</p>
3553 <p>You could tell your SMTP server to not lookup any addresses if you are
3554 not keen on checking the sender addresses. This problem typically
3555 occurs if your mail server is not checking the sender addresses, but
3556 your local server is.</p>
3558 <p>Or you could declare <code>antispam 451</code>.</p>
3560 <p>Or, you could check your nameserver configuration and query logs for
3563 <p>All these issues are not related to fetchmail directly.</p>
3566 <h2><a name="O13">O13. I want timestamp information in my fetchmail logs.</a></h2>
3568 <p>Write a <code>preconnect</code> command in your configuration file that
3569 does something like "date >> $HOME/Procmail/fetchmail.log".</p>
3572 <table width="100%" cellpadding="0" summary="Canned page footer">
3574 <td width="30%">Back to <a href="index.html">Fetchmail Home
3576 <td width="30%" align="right">$Date$</td>
3581 <address>Eric S. Raymond <a
3582 href="mailto:esr@thyrsus.com"><esr@thyrsus.com></a><br />
3583 Matthias Andree</address>