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15 <td width="30%">Back to <a href="index.html">Fetchmail Home
17 <td width="30%" align="right">$Date: 2004/01/13 08:46:00 $</td>
22 <h1>Frequently Asked Questions About Fetchmail</h1>
24 <p>Before reporting any bug, please read <a href="#G3">G3</a> for
25 advice on how to include diagnostic information that will get your
26 bug fixed as quickly as possible.</p>
28 <p>If you have a question or answer you think ought to be added to
29 this FAQ list, mail it to fetchmail's maintainer, Eric S. Raymond,
30 at <a href="mailto:esr@thyrsus.com">esr@thyrsus.com</a>.</p>
32 <h1>General questions:</h1>
34 <a href="#G1">G1. What is fetchmail and why should I bother?</a><br/>
35 <a href="#G2">G2. Where do I find the latest FAQ and fetchmail sources?</a><br/>
36 <a href="#G3">G3. I think I've found a bug. Will you fix it?</a><br/>
37 <a href="#G4">G4. I have this idea for a neat feature. Will you add it?</a><br/>
38 <a href="#G5">G5. I want to make fetchmail behave like Outlook Express.</a><br/>
39 <a href="#G6">G6. Is there a mailing list for exchanging tips?</a><br/>
40 <a href="#G7">G7. So, what's this I hear about a fetchmail paper?</a><br/>
41 <a href="#G8">G8. What is the best server to use with fetchmail?</a><br/>
42 <a href="#G9">G9. What is the best mail program to use with fetchmail?</a><br/>
43 <a href="#G10">G10. How can I avoid sending my password en clair?</a><br/>
44 <a href="#G11">G11. Is any special configuration needed to use a dynamic IP address?</a><br/>
45 <a href="#G12">G12. Is any special configuration needed to use firewalls?</a><br/>
46 <a href="#G13">G13. Is any special configuration needed to <em>send</em> mail?</a><br/>
47 <a href="#G14">G14. Is fetchmail Y2K-compliant?</a><br/>
48 <a href="#G15">G15. Is there a way in fetchmail to support disconnected IMAP mode?</a><br/>
49 <a href="#G16">G16. How will fetchmail perform under heavy loads?</a><br/>
52 <h1>Build-time problems:</h1>
54 <a href="#B1">B1. Make coughs and dies when building on FreeBSD.</a><br/>
55 <a href="#B2">B2. Lex bombs out while building the fetchmail lexer.</a><br/>
56 <a href="#B3">B3. I get link failures when I try to build fetchmail.</a><br/>
57 <a href="#B4">B4. I get build failures in the intl directory.</a><br/>
59 <h1>Fetchmail configuration file grammar questions:</h1>
61 <a href="#F1">F1. Why does my old .fetchmailrc no longer work?</a><br/>
62 <a href="#F2">F2. The .fetchmailrc parser won't accept my all-numeric user name.</a><br/>
63 <a href="#F3">F3. The .fetchmailrc parser won't accept my host or username beginning with 'no'.</a><br/>
64 <a href="#F4">F4. I'm getting a 'parse error' message I don't understand.</a><br/>
66 <h1>Configuration questions:</h1>
68 <a href="#C1">C1. Why do I need a .fetchmailrc when running as root
69 on my own machine?</a><br/>
70 <a href="#C2">C2. How can I arrange for a fetchmail daemon to get
71 killed when I log out?</a><br/>
72 <a href="#C3">C3. How do I know what interface and address to use
73 with --interface?</a><br/>
74 <a href="#C4">C4. How can I set up support for sendmail's anti-spam
76 <a href="#C5">C5. How can I poll some of my mailboxes more/less
77 often than others?</a><br/>
78 <a href="#C6">C6. Fetchmail works OK started up manually, but not
79 from an init script.</a><br/>
80 <a href="#C7">C7. How can I forward mail to another
84 <h1>How to make fetchmail play nice with various MTAs:</h1>
86 <a href="#T1">T1. How can I use fetchmail with sendmail?</a><br/>
87 <a href="#T2">T2. How can I use fetchmail with qmail?</a><br/>
88 <a href="#T3">T3. How can I use fetchmail with exim?</a><br/>
89 <a href="#T4">T4. How can I use fetchmail with smail?</a><br/>
90 <a href="#T5">T5. How can I use fetchmail with SCO's MMDF?</a><br/>
91 <a href="#T6">T6. How can I use fetchmail with Lotus Notes?</a><br/>
92 <a href="#T7">T7. How can I use fetchmail with Courier IMAP?</a><br/>
93 <a href="#T8">T8. How can I use fetchmail with vbmailshield?</a><br/>
95 <h1>How to make fetchmail work with various servers:</h1>
97 <a href="#S1">S1. How can I use fetchmail with qpopper?</a><br/>
98 <a href="#S2">S2. How can I use fetchmail with Microsoft Exchange?</a><br/>
99 <a href="#S3">S3. How can I use fetchmail with HP OpenMail?</a><br/>
100 <a href="#S4">S4. How can I use fetchmail with Novell GroupWise?</a><br/>
101 <a href="#S5">S5. How can I use fetchmail with InterChange?</a><br/>
102 <a href="#S6">S6. How can I use fetchmail with MailMax?</a><br/>
103 <a href="#S7">S7. How can I use fetchmail with FTGate?</a><br/>
105 <h1>How to fetchmail work with specific ISPs:</h1>
107 <a href="#I1">I1. How can I use fetchmail with Compuserve RPA?</a><br/>
108 <a href="#I2">I2. How can I use fetchmail with Demon Internet's SDPS?</a><br/>
109 <a href="#I3">I3. How can I use fetchmail with usa.net's servers?</a><br/>
110 <a href="#I4">I4. How can I use fetchmail with geocities POP3 servers?</a><br/>
111 <a href="#I5">I5. How can I use fetchmail with Hotmail or Lycos Webmail?</a><br/>
112 <a href="#I6">I6. How can I use fetchmail with MSN?</a><br/>
113 <a href="#I7">I7. How can I use fetchmail with SpryNet?</a><br/>
114 <a href="#I8">I8. How can I use fetchmail with comcast.net?</a><br/>
116 <h1>How to set up well-known security and authentication
119 <a href="#K1">K1. How can I use fetchmail with SOCKS?</a><br/>
120 <a href="#K2">K2. How can I use fetchmail with IPv6 and IPsec?</a><br/>
121 <a href="#K3">K3. How can I get fetchmail to work with ssh?</a><br/>
122 <a href="#K4">K4. What do I have to do to use the IMAP-GSS protocol?</a><br/>
123 <a href="#K5">K5. How can I use fetchmail with SSL?</a><br/>
124 <a href="#K6">K6. How can I tell fetchmail not to try TLS if the server
125 advertises it?</a><br/>
127 <h1>Runtime fatal errors:</h1>
129 <a href="#R1">R1. Fetchmail isn't working, and -v shows 'SMTP
130 connect failed' messages.</a><br/>
131 <a href="#R2">R2. When I try to configure an MDA, fetchmail doesn't
133 <a href="#R3">R3. Fetchmail dumps core when given an invalid rc
135 <a href="#R4">R4. Fetchmail dumps core in -V mode, but operates
136 normally otherwise.</a><br/>
137 <a href="#R5">R5. Running fetchmail in daemon mode doesn't
139 <a href="#R6">R6. Fetchmail randomly dies with socket errors.</a><br/>
140 <a href="#R7">R7. Fetchmail running as root stopped working after
141 an OS upgrade</a><br/>
142 <a href="#R8">R8. Fetchmail is timing out after fetching certain
143 messages but before deleting them</a><br/>
144 <a href="#R9">R9. Fetchmail is timing out during message fetches</a><br/>
145 <a href="#R10">R10. Fetchmail is dying with SIGPIPE.</a><br/>
146 <a href="#R11">R11. My server is hanging or emitting errors on CAPA.</a><br/>
147 <h1>Hangs and lockups:</h1>
149 <a href="#H1">H1. Fetchmail hangs when used with pppd.</a><br/>
150 <a href="#H2">H2. Fetchmail hangs during the MAIL FROM
152 <a href="#H3">H3. Fetchmail hangs while fetching mail.</a><br/>
155 <h1>Disappearing mail:</h1>
157 <a href="#D1">D1. I think I've set up fetchmail correctly, but I'm
158 not getting any mail.</a><br/>
159 <a href="#D2">D2. All my mail seems to disappear after a dropped
161 <a href="#D3">D3. Mail that was being fetched when I interrupted my
162 fetchmail seems to have been vanished.</a><br/>
165 <h1>Multidrop-mode problems:</h1>
167 <a href="#M1">M1. I've declared local names, but all my multidrop
168 mail is going to root anyway.</a><br/>
169 <a href="#M2">M2. I can't seem to get fetchmail to route to a local
170 domain properly.</a><br/>
171 <a href="#M3">M3. I tried to run a mailing list using multidrop,
172 and I have a mail loop!</a><br/>
173 <a href="#M4">M4. My multidrop fetchmail seems to be having DNS
175 <a href="#M5">M5. I'm seeing long DNS delays before each message is
177 <a href="#M6">M6. How do I get multidrop mode to work with
179 <a href="#M7">M7. Multidrop mode isn't parsing envelope addresses
180 from my Received headers as it should.</a><br/>
181 <a href="#M8">M8. Users are getting multiple copies of
185 <h1>Mangled mail:</h1>
187 <a href="#X1">X1. Spurious blank lines are appearing in the headers
188 of fetched mail.</a><br/>
189 <a href="#X2">X2. My mail client can't see a Subject
191 <a href="#X3">X3. Messages containing "From" at start of line are
192 being split.</a><br/>
193 <a href="#X4">X4. My mail is being mangled in a new and different
195 <a href="#X5">X5. Using POP3, retrievals seems to be fetching too
197 <a href="#X6">X6. My mail attachments are being dropped or
199 <a href="#X7">X7. Some mail attachments are hanging
201 <a href="#X8">X8. A spurious ) is being appended to my
204 <h1>Other problems:</h1>
206 <a href="#O1">O1. The --logfile option doesn't work if the logfile
207 doesn't exist.</a><br/>
208 <a href="#O2">O2. Every time I get a POP or IMAP message the header
209 is dumped to all my terminal sessions.</a><br/>
210 <a href="#O3">O3. Does fetchmail reread its rc file every poll
212 <a href="#O4">O4. Why do deleted messages show up again when I take
213 a line hit while downloading?</a><br/>
214 <a href="#O5">O5. Why is fetched mail being logged with my name,
215 not the real From address?</a><br/>
216 <a href="#O6">O6. I'm seeing long sendmail delays or hangs near the
217 start of each poll cycle.</a><br/>
218 <a href="#O7">O7. Why doesn't fetchmail deliver mail in date-sorted
220 <a href="#O8">O8. I'm using pppd. Why isn't my monitor option
222 <a href="#O9">O9. Why does fetchmail keep retrieving the same
223 messages over and over?</a><br/>
224 <a href="#O10">O10. Why is the received date on all my messages the
226 <a href="#O11">O11. I keep getting messages that say "Repoll
227 immediately" in my logs.</a><br/>
228 <a href="#O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a><br/>
229 <a href="#O13">O13. I want timestamp information in my fetchmail logs.</a>
234 <h2><a id="G1" name="G1">G1. What is fetchmail and why should I
237 <p>Fetchmail is a one-stop solution to the remote mail retrieval
238 problem for Unix machines, quite useful to anyone with an
239 intermittent PPP or SLIP connection to a remote mailserver. It can
240 collect mail using any variant of POP or IMAP and forwards via port
241 25 to the local SMTP listener, enabling all the normal
242 forwarding/filtering/aliasing mechanisms that would apply to local
243 mail or mail arriving via a full-time TCP/IP connection.</p>
245 <p>Fetchmail is not a toy or a coder's learning exercise, but an
246 industrial-strength tool capable of transparently handling every
247 retrieval demand from those of a simple single-user ISP connection
248 up to mail retrieval and rerouting for an entire client domain.
249 Fetchmail is easy to configure, unobtrusive in operation, powerful,
250 feature-rich, and well documented.</p>
252 <p>Fetchmail is <a href="http://www.opensource.org">open-source</a>
253 software. The openness of the sources is the strongest assurance of
254 quality you can have. Extensive peer review by a large,
255 multi-platform user community has shown that fetchmail is as near
256 bulletproof as the underlying protocols permit.</p>
258 <p>Fetchmail is licensed under the <a
259 href="http://gnu.org//copyleft/gpl.html">GNU General Public
262 <p>If you found this FAQ in the distribution, see the README for
263 fetchmail's full feature list.</p>
266 <h2><a id="G2" name="G2">G2. Where do I find the latest FAQ and
267 fetchmail sources?</a></h2>
269 <p>The latest HTML FAQ is available alongside the latest fetchmail
270 sources at the fetchmail home page: <a
271 href="http://fetchmail.berlios.de/">http://fetchmail.berlios.de/</a>.
272 You can also usually find both in the <a
273 href="http://sunsite.unc.edu/pub/Linux/system/mail/pop/!INDEX.html">
274 POP mail tools directory on Sunsite</a>.</p>
276 <p>A text dump of this FAQ is included in the fetchmail
277 distribution. Because it freezes at distribution release time, it
278 may not be completely current.</p>
281 <h2><a id="G3" name="G3">G3. I think I've found a bug. Will you fix
284 <p>Yes I will, provided you include enough diagnostic information
285 for me to go on. Send bugs to <a
286 href="mailto:fetchmail-friends@ccil.org">fetchmail-friends</a>.
287 When reporting bugs, please include the following:</p>
290 <li>Your operating system.</li>
292 <li>Your compiler version, if you built from source; otherwise, the
293 name and origin of the RPM or other binary package you
296 <li>A copy of your POP or IMAP server's greeting line.</li>
298 <li>The name and version of the SMTP listener or MDA you are
301 <li>Any command-line options you used.</li>
303 <li>The output of fetchmail -V called with whatever other
304 command-line options you used.</li>
307 <p>If you have FTP access to your remote mail account, and you have
308 any suspicion that the bug was triggered by a particular message,
309 please include a copy of the message that triggered the bug.</p>
311 <p>Often, the first thing I will do when you report a bug is tell
312 you to upgrade to the newest version of fetchmail, and then see if
313 the problem reproduces. So you'll probably save us both time if you
314 upgrade and test with the latest version <em>before</em> sending in
317 <p>If your bug is something that used to work but stopped working
318 when you upgraded, then you can help pin the bug down by trying <a
319 href="ftp://ftp.ccil.org/pub/esr/fetchmail/">intermediate versions
320 of fetchmail</a> until you identify the revision that broke your
321 feature. The smart way to do this is by binary search on the
322 version sequence. First, try the version halfway between your last
323 good one and the current one. If it works, the failure was
324 introduced in the upper half of the sequence; if it doesn't, the
325 failure was introduced in the lower half. Now bisect that half in
326 the same way. In a very few tries, you should be able to identify
327 the exact adjacent pair of versions between which your bug was
328 introduced -- and with information like that, I can usually come up
329 with a fix very quickly.</p>
331 <p>Another useful thing you can do, if you're using POP3, is to
332 test for IMAP4 support on your mailserver using the autoprobe
333 function of fetchmailconf. If you have IMAP4, and fetchmailconf
334 doesn't tell you it's broken, switch immediately. POP3 is a weak,
335 poorly-designed protocol with chronic problems, and the later
336 versions after RFC1725 actually get worse rather than better.
337 Changing over to IMAP4 may well make your problem go away -- and if
338 your ISP doesn't have IMAP4 support, bug them to supply it.</p>
340 <p>It is helpful if you include your .fetchmailrc file, but not
341 necessary unless your symptom seems to involve an error in
342 configuration parsing. If you do send in your .fetchmailrc, mask
343 the passwords first!</p>
345 <p>If fetchmail seems to run and fetch mail, but the headers look
346 mangled (that is, headers are missing or blank lines are inserted
347 in the headers) then read the FAQ items in section <a
348 href="#X1">X</a> before submitting a bug report. Pay special
349 attention to the item on <a href="#generic_mangling">diagnosing
350 mail mangling</a>. There are lots of ways for other programs in the
351 mail chain to screw up that look like fetchmail's fault, but you
352 may be able to fix these by tweaking your configuration.</p>
354 <p>A transcript of the failed session with -v -v (yes, that's
355 <em>two</em> -v options, enabling debug mode) will almost always be
356 useful. It is very important that the transcript include your
357 POP/IMAP server's greeting line, so I can identify it in case of
358 server problems. This transcript will not reveal your passwords,
359 which are specially masked out precisely so transcripts can be
362 <p>If you upgraded your fetchmail and something broke, you should
363 include session transcripts with -v -v of both the working and
364 failing versions. Very often, the source of the problem can
365 instantly identified by looking at the differences in protocol
368 <p>If the bug involves a core dump or hang, a gdb stack trace is
369 good to have. (Bear in mind that you can attach gdb to a running
370 but hung process by giving the process ID as a second argument.)
371 You will need to reconfigure with:</p>
374 CFLAGS=-g LDFLAGS=" " ./configure
377 <p>Then rebuild in order to generate a version that can be
380 <p>Best of all is a mail file which, when fetched, will reproduce
381 the bug under the latest (current) version.</p>
383 <p>Any bug I can reproduce will usually get fixed very quickly,
384 often within 48 hours. Bugs I can't reproduce are a crapshoot. If
385 the solution isn't obvious when I first look, it may evade me for a
386 long time (or to put it another way, fetchmail is well enough
387 tested that the easy bugs have long since been found). So if you
388 want your bug fixed rapidly, it is not just sufficient but nearly
389 <em>necessary</em> that you give me a way to reproduce it.</p>
392 <h2><a id="G4" name="G4">G4. I have this idea for a neat feature.
393 Will you add it?</a></h2>
395 <p>Probably not. Most of the feature suggestions I get are for ways
396 to set various kinds of administrative policy or add more spam
397 filtering (the most common one, which I used to get about four
398 million times a week and got <em>really</em> tired of, is for
399 tin-like kill files).</p>
401 <p>You can do spam filtering better with procmail or maildrop on
402 the server side and (if you're the server sysadmin) sendmail.cf
403 domain exclusions. If you really want fetchmail to do it from the
404 client side, yse a <code>preconnect</code> command to call
405 <a href='http://mailfilter.sourceforge.net/'>mailfilter</a>.</p>
407 <p>You can do other policy things better with the
408 <code>mda</code> option and script wrappers around fetchmail. If
409 it's a prime-time-vs.-non-prime-time issue, ask yourself whether a
410 wrapper script called from crontab would do the job.</p>
412 <p>I'm not going to do these; fetchmail's job is transport, not
413 policy, and I refuse to change it from doing one thing well to
414 attempting many things badly. One of my objectives is to keep
415 fetchmail simple so it stays reliable.</p>
417 <p>For reasons fetchmail doesn't have other commonly-requested
418 features (such as password encryption, or multiple concurrent polls
419 from the same instance of fetchmail) see <a
420 href="esrs-design-notes.html">ESR's design
421 notes</a>. Note that this document is partially obsoleted by the
422 <a href="design-notes.html">updated design notes.</a></p>
424 <p>Fetchmail is a mature project, no longer in constant active
425 development. It is no longer my top project, and I am going to be
426 quite reluctant to add features that might either jeopardize its
427 stability or involve me in large amounts of coding.</p>
429 <p>All that said, if you have a feature idea that really is about a
430 transport problem that can't be handled anywhere but fetchmail, lay
431 it on me. I'm very accommodating about good ideas.</p>
434 <h2><a id="G5" name="G5">G5. I want to make fetchmail behave like
435 Outlook Express.</a></h2>
437 <p>The second-most-requested feature for fetchmail, after
438 content-based filtering, is the ability to have it remove messages
439 from a maildrop after N days, typically to be used with the
440 <code>keep</code> option as a sort of poor man's newsgroup
441 facility. Microsoft's Outlook Express supports this.</p>
443 <p>This feature won't be added either. Repeat after me: fetchmail's
444 job is transport, not policy. If you want this, write a Perl or
445 Python script, to be run from a cron job, that deletes old messages
446 off your maildrop. Send it to me and I'll put it in the contrib
450 <h2><a id="G6" name="G6">G6. Is there a mailing list for exchanging
453 <p>There is a fetchmail-friends list
454 (fetchmail-friends@lists.ccil.org) for people who want to discuss
455 fixes and improvements in fetchmail and help co-develop it. It's a
456 MailMan list, which you can sign up for at <a
457 href="http://lists.ccil.org/mailman/listinfo/fetchmail-friends">http://lists.ccil.org/mailman/listinfo/fetchmail-friends</a>.
458 There is also an announcements-only list,
459 fetchmail-announce@lists.ccil.org, which you can sign up for at <a
460 href="http://lists.ccil.org/mailman/listinfo/fetchmail-announce">http://lists.ccil.org/mailman/listinfo/fetchmail-announce</a>.</p>
463 <h2><a id="G7" name="G7">G7. So, what's this I hear about a
464 fetchmail paper?</a></h2>
466 <p>The fetchmail development was also a sociological experiment, an
467 extended test to see if my theory about the critical features of
468 the Linux development model is correct.</p>
470 <p>The experiment was a success. I wrote a paper about it titled <a
471 href="http://www.catb.org/~esr/writings/cathedral.html">The
472 Cathedral and the Bazaar</a> which was first presented at Linux
473 Kongress '97 in Bavaria and very well received there. It was also
474 given at Atlanta Linux Expo, Linux Pro '97 in Warsaw, and the first
475 Perl Conference, at UniForum '98, and was the basis of an invited
476 presentation at Usenix '98. The folks at Netscape tell me it helped
478 href="http://www.netscape.com/newsref/pr/newsrelease558.html">give
479 away the source for Netscape Communicator</a>.</p>
481 <p>If you're reading a non-HTML dump of this FAQ, you can find the
482 paper on the Web with a search for that title.</p>
485 <h2><a id="G8" name="G8">G8. What is the best server to use with
488 <p>The short answer: IMAP 2000 running over Unix.</p>
490 <p>Here's a longer answer:</p>
492 <p>Fetchmail will work with any POP, IMAP, ETRN, or ODMR server
493 that conforms to the relevant RFCs (and even some outright broken
494 ones like <a href="#S2">Microsoft Exchange</a> and <a
495 href="#S6">Novell GroupWise</a>). This doesn't mean it works
496 equally well with all, however. POP2 servers, and POP3 servers
497 without LAST, limit fetchmail's capabilities in various ways
498 described on the manual page.</p>
500 <p>Most modern Unixes (and effectively all Linux/*BSD systems) come
501 with POP3 support preconfigured (but beware of the horribly broken
502 POP3 server mentioned in <a href="#D2">D2</a>). An increasing
503 minority also feature IMAP (you can detect IMAP support by running
504 fetchmail in AUTO mode, or by using the 'Probe for supported
505 protocols' function in the fetchmailconf utility).</p>
507 <p>If you have the option, we recommend using or installing an
508 IMAP4rev1 server; it has the best facilities for tracking message
509 'seen' states. It also recovers from interrupted connections more
510 gracefully than POP3, and enables some significant performance
511 optimizations. The new <a
512 href="ftp://ftp.cac.washington.edu/imap/imap.tar.Z">IMAP 2000</a>
513 is particularly nice, as it supports CRAM-MD5 so you don't have to
514 ship your mail password over the net en clair (fetchmail
515 autodetects this capability). Older versions had support for GSSAPI
516 giving a similar effect.</p>
518 <p>Don't be fooled by NT/Exchange propaganda. M$ Exchange is just
519 plain broken (see item <a href="#S2">S2</a>) and NT cannot handle
520 the sustained load of a high-volume remote mail server. Even
521 Microsoft itself knows better than to try this; their own Hotmail
522 service runs over Solaris! For extended discussion, see John
523 Kirch's excellent <a href="http://unix-vs-nt.org/kirch/">white
524 paper</a> on Unix vs. NT performance.</p>
526 <p>Source for a high-quality supported implementation of POP is
527 available from the <a
528 href="ftp://ftp.qualcomm.com/eudora/servers/unix/popper/">Eudora
529 FTP site</a>. Don't use 2.5, which has a rather restrictive
530 license. The 2.5.2 version appears to restore the open-source
531 license of previous versions.</p>
534 <h2><a id="G9" name="G9">G9. What is the best mail program to use
535 with fetchmail?</a></h2>
537 <p>Fetchmail will work with all popular <a href="#T1">mail
538 transport programs</a>. It also doesn't care which user agent you
539 use, and user agents are as a rule almost equally indifferent to
540 how mail is delivered into your system mailbox. So any of the
541 popular Unix mail agents -- <a
542 href="http://www.myxa.com/old/elm.html">elm</a>, <a
543 href="http://www.washington.edu/pine/">pine</a>, <a
544 href="http://www.cs.indiana.edu/docproject/mail/mh.html">mh</a>, or
545 <a href="http://www.mutt.org">mutt</a> -- will work fine with
548 <p>All this having been said, I can't resist putting in a discreet
549 plug for <a href="http://www.mutt.org">mutt</a>. My own personal
550 mail setup is sendmail plus fetchmail plus mutt. Mutt's interface
551 is only a little different from that of its now-moribund ancestor
552 elm, but its excellent handling of MIME and PGP put it in a class
553 by itself. You won't need its built-in POP3 support, though; most
554 of the mutt developers will cheerfully admit that fetchmail's is
558 <h2><a id="G10" name="G10">G10. How can I avoid sending my password
561 <p>Depending on what your mail server you are talking to, this
562 ranges from trivial to impossible. It may even be next to
565 <p>Most people use fetchmail over phone wires (whether plain old
566 copper or DSL), which are hard to tap. Anybody with the skill and
567 resources to do this could get into your server mailbox with much less
568 effort by subverting the server host. So if your provider setup is
569 phone-company wire going straight into a service box, you probably
570 don't need to worry.</p>
572 <p>In general there is little point in trying to secure your fetchmail
573 transaction unless you trust the security of the server host you are
574 retrieving mail from. Your vulnerability is more likely to be an
575 insecure local network on the server end (e.g. to somebody with a
576 TCP/IP packet sniffer intercepting Ethernet traffic between the modem
577 concentrator or DSL POP you dial in to and the mailserver host).</p>
579 <p>Having realized this, you need to ask whether password
580 encryption alone will really address your security exposure. If you
581 think you might be snooped between server and client, it's better
582 to use end-to-end encryption on your whole mail stream so none of
583 it can be read. One of the advantages of fetchmail over
584 conventional SMTP-push delivery is that you may be able to arrange
585 this by using ssh(1); see <a href="#K3">K3</a>.</p>
587 <p>Note that ssh is not a complete privacy solution either, as your
588 mail could have been snooped in transit to your POP server from
589 wherever it originated. For best security, agree with your
590 correspondents to use a tool such as <a
591 href="http://www.gnupg.org/">GPG</a> (Gnu Privacy Guard) or PGP
592 (Pretty Good Privacy).</p>
594 <p>If ssh/sshd isn't available, or you find it too complicated for
595 you to set up, password encryption will at least keep a malicious
596 cracker from deleting your mail, and require him to either tap your
597 connection continuously or crack root on the server in order to
600 <p>You can deduce what encryptions your mail server has available
601 by looking at the server greeting line (and, for IMAP, the response
602 to a CAPABILITY query). Do a <code>fetchmail -v</code> to see
603 these, or telnet direct to the server port (110 for POP3, 143 for
606 <p>If your mailserver is using IMAP 2000, you'll have CRAM-MD5
607 support built in. Fetchmail autodetects this; you can skip the rest
610 <p>The POP3 facility you are most likely to have available is APOP.
611 This is a POP3 feature supported by many servers (fetchmailconf's
612 autoprobe facility will detect it and tell you if you have it). If
613 you see something in the greeting line that looks like an
614 angle-bracket-enclosed Internet address with a numeric left-hand
615 part, that's an APOP challenge (it will vary each time you log in).
616 You can register a secret on the host (using
617 <code>popauth(8)</code> or some program like it). Specify the
618 secret as your password in your .fetchmailrc; it will be used to
619 encrypt the current challenge, and the encrypted form will be sent
620 back the the server for verification.</p>
622 <p>Alternatively, you may have Kerberos available. This may require
623 you to set up some magic files in your home directory on your
624 client machine, but means you can omit specifying any password at
627 <p>Fetchmail supports two different Kerberos schemes. One is a POP3
628 variant called KPOP; consult the documentation of your mail server
629 to see if you have it (one clue is the string "krb-IV" in the
630 greeting line on port 110). The other is an IMAP and POP3 facility
631 described by RFC1731 and RFC1734. You can tell if this one is
632 present by looking for AUTH=KERBEROS_V4 in the CAPABILITY
635 <p>If you are fetching mail from a CompuServe POP3 account, you can
636 use their RPA authentication (which works much like APOP). See <a
637 href="#I1">I1</a> for details. If you are fetching mail from
638 Microsoft Exchange using IMAP, you will be able to use NTLM.</p>
640 <p>Your POP3 server may have the RFC1938 OTP capability to use
641 one-time passwords (if it doesn't, you can get OTP patches for the
642 2.2 version of the Qualcomm popper from <a href="#cmetz">Craig
643 Metz</a>). To check this, look for the string "otp-" in the
644 greeting line. If you see it, and your fetchmail was built with
645 OPIE support compiled in (see the distribution INSTALL file),
646 fetchmail will detect it also. When using OTP, you will specify a
647 password but it will not be sent en clair.</p>
649 <p>You can get both POP3 and IMAP OTP patches from <a id="cmetz"
650 name="cmetz">Craig Metz</a> at <a
651 href="http://www.inner.net/opie">http://www.inner.net/opie</a>.</p>
653 <p>These patches use a SASL authentication method named "X-OTP"
654 because there is not currently a standard way to do this; fetchmail
655 also uses this method, so the two will interoperate happily. They
656 better, because this is how Craig gets his mail ;-)</p>
658 <p>Finally, you can use <a href="#K5">SSL</a> for complete
659 end-to-end encryption if you have an SSL-enabled mailserver.</p>
662 <h2><a id="G11" name="G11">G11. Is any special configuration needed
663 to use a dynamic IP address?</a></h2>
665 <p>Yes. In order to avoid giving indigestion to certain picky MTAs
666 (notably <a href="#T3">exim</a>), fetchmail always makes the RCPT
667 TO address it feeds the MTA a fully qualified one with a hostname
668 part. Normally it does this by appending @ and "localhost", but
669 when you are using Kerberos or ETRN mode it will append @ and your
670 machine's fully-qualified domain name (FQDN).</p>
672 <p>Appending the FQDN can create problems when fetchmail is running
673 in daemon mode and outlasts the dynamic IP address assignment your
674 client machine had when it started up.</p>
676 <p>Since the new IP address (looked up at RCPT TO interpretation
677 time) doesn't match the original, the most benign possible result
678 is that your MTA thinks it's seeing a relaying attempt and refuses.
679 More frequently, fetchmail will try to connect to a nonexistent
680 host address and time out. Worst case, you could up forwarding your
681 mail to the wrong machine!</p>
683 <p>Use the <code>smtpaddress</code> option to force the appended
684 hostname to one with a (fixed) IP address of 127.0.0.1 in your
685 <code>/etc/hosts</code>. (The name 'localhost' will usually work;
686 or you can use the IP address itself).</p>
688 <p>Only one fetchmail option interacts directly with your IP
689 address, '<code>interface</code>'. This option can be used to set
690 the gateway device and restrict the IP address range fetchmail will
691 use. Such a restriction is sometimes useful for security reasons,
692 especially on multihomed sites. See <a href="#C3">C3</a>.</p>
694 <p>I recommend against trying to set up the <code>interface</code>
695 option when initially developing your poll configuration -- it's
696 never necessary to do this just to get a link working. Get the link
697 working first, observe the actual address range you see on
698 connections, and add an <code>interface</code> option (if you need
701 <p>You can't use ETRN if you have a dynamic IP address (your ISP
702 changes your IP address occasionally, possibly with every connect).
703 You need to have your own registered domain and a definite IP
704 address registered for that domain. The server needs to be
705 configured to accept mail for your domain but then queue it to
706 forward to your machine. ETRN just tells to server to flush its
707 queue for your domain. Fetchmail doesn't actually get the mail in
710 <p>You can use On-Demand Mail Relay (ODMR) with a dynamic IP
711 address; that's what it was designed for, and it provides
712 capabilities very similar to ETRN. Unfortunately ODMR servers are
713 not yet widely deployed, as of early 2001.</p>
715 <p>If you're using a dynamic-IP configuration, one other
716 (non-fetchmail) problem you may run into with outgoing mail is that
717 some sites will bounce your email because the hostname your giving
718 them isn't real (and doesn't match what they get doing a reverse
719 DNS on your dynamically-assigned IP address). If this happens, you
720 need to hack your sendmail so it masquerades as your host.
727 <p>in your <code>sendmail.cf</code> will work, or you can set</p>
730 MASQUERADE_AS(smarthost.here)
733 <p>in the m4 configuration and do a reconfigure. (In both cases,
734 replace <code>smarthost.here</code> with the actual name of your
735 mailhost.) See the <a
736 href="http://www.lege.com/sendmail-FAQ.txt">sendmail FAQ</a> for
740 <h2><a id="G12" name="G12">G12. Is any special configuration needed
741 to use firewalls?</a></h2>
743 <p>No. You can use fetchmail with SOCKS, the standard tool for
744 indirecting TCP/IP through a firewall. You can find out about
745 SOCKS, and download the SOCKS software including server and client
746 code, at the <a href="http://www.socks.nec.com/">SOCKS distribution
749 <p>The specific recipe for using fetchmail with a firewall is at <a
750 href="#K1">K1</a></p>
753 <h2><a id="G13" name="G13">G13. Is any special configuration needed
754 to <em>send</em> mail?</a></h2>
756 <p>A user asks: but how do we send mail out to the POP3 server? Do
757 I need to implement another tool or will fetchmail do this too?</p>
759 <p>Fetchmail only handles the receiving side. The sendmail or other
760 preinstalled MTA on your client machine will handle sending mail
761 automatically; it will ship mail that is submitted while the
762 connection is active, and put mail that is submitted while the
763 connection is inactive into the outgoing queue.</p>
765 <p>Normally, sendmail is also run periodically (every 15 minutes on
766 most Linux systems) in a mode that tries to ship all the mail in
767 the outgoing queue. If you have set up something like pppd to
768 automatically dial out when your kernel is called to open a TCP/IP
769 connection, this will ensure that the mail gets out.</p>
772 <h2><a id="G14" name="G14">G14. Is fetchmail
773 Y2K-compliant?</a></h2>
775 <p>Fetchmail is fully Y2K-compliant.</p>
777 <p>Fetchmail could theoretically have problems when the 32-bit
778 time_t counters roll over in 2038, but I doubt it. Timestamps
779 aren't used for anything but log entry generation. Anyway, if you
780 aren't running on a 64-bit machine by then, you'll deserve to
784 <h2><a id="G15" name="G15">G15. Is there a way in fetchmail to
785 support disconnected IMAP mode?</a></h2>
787 <p>No. Fetchmail is a mail transport agent, best understood as a
788 protocol gateway between POP3/IMAP servers and SMTP. Disconnected
789 operation requires an elaborate interactive client. It's a very
790 different problem.</p>
793 <h2><a id="G16" name="G16">G16. How will fetchmail perform under
794 heavy loads?</a></h2>
796 <p>Fetchmail streams message bodies line-by-line; the most core it
797 ever requires per message is enough memory to hold the RFC822
798 header, and that storage is freed when body processing begins. It
799 is, accordingly, quite economical in its use of memory.</p>
801 <p>After startup time, a fetchmail running in daemon mode stats its
802 configuration file once per poll cycle to see whether it has
803 changed and should be rescanned. Other than that, a fetchmail in
804 normal operation doesn't touch the disk at all; that job is left up
805 to the MTA or MDA the fetchmail talks to.</p>
807 <p>Fetchmail's performance is usually bottlenecked by latency on
808 the POP server or (less often) on the TCP/IP link to the server.
809 This is not a problem readily solved by tuning fetchmail, or even
810 by buying more TCP/IP capacity (which tends to improve bandwidth
811 but not necessarily latency).</p>
814 <h2><a id="B1" name="B1">B1. Make coughs and dies when building on
817 <p>The vendor-supplied make on FreeBSD systems can only be used
818 within FreeBSD's "scope", e.g. the ports collection. Type "gmake"
819 to run GNU make and better things will happen.</p>
822 <h2><a id="B2" name="B2">B2. Lex bombs out while building the
823 fetchmail lexer.</a></h2>
825 <p>In the immortal words of Alan Cox the last time this came up:
826 "Take the Solaris lex and stick it up the backside of a passing
827 Sun salesman, then install <a
828 href="ftp://ftp.gnu.org/pub/non-gnu/flex/">flex</a> and use that.
829 All will be happier."</p>
831 <p>I couldn't have put it better myself, and ain't going to try
834 <p>(The same problem has been reported under HP-UX v10.20 and
838 <h2><a id="B3" name="B3">B3. I get link failures when I try to
839 build fetchmail.</a></h2>
841 <p>If you get errors resembling these</p>
844 mxget.o(.text+0x35): undefined referenceto '__res_search'
845 mxget.o(.text+0x99): undefined reference to '__dn_skipname'
846 mxget.o(.text+0x11c): undefined reference to '__dn_expand'
847 mxget.o(.text+0x187): undefined reference to '__dn_expand'
848 make: *** [fetchmail] Error 1
851 <p>then you must add "-lresolv" to the LOADLIBS line in your
852 Makefile once you have installed the 'bind' package.</p>
854 <p>If you get link errors involving <tt>dcgettext</tt>, like
858 rcfile_y.o: In function 'yyparse':
859 rcfile_y.o(.text+0x3aa): undefined reference to 'dcgettext__'
860 rcfile_y.o(.text+0x4f2): undefined reference to 'dcgettext__'
861 rcfile_y.o(.text+0x5ee): undefined reference to 'dcgettext__'
862 rcfile_y.o: In function 'yyerror':
863 rcfile_y.o(.text+0xc7c): undefined reference to 'dcgettext__'
864 rcfile_y.o(.text+0xcc8): undefined reference to 'dcgettext__'
865 rcfile_y.o(.text+0xdf9): more undefined references to 'dcgettext__' follow
868 <p>reconfigure with <tt>configure --with-included-gettext</tt>.
869 This is due to some brain-damage in the GNU internationalization
873 <h2><a id="B4" name="B4">B4. I get build failures in the intl
876 <p>Reconfigure with <tt>--disable-nls</tt> and recompile.</p>
878 <p>GNU gettext is an overengineered, fragile pile of crap. I have
879 teetered on the brink of removing support for it entirely several
883 <h2><a id="F1" name="F1">F1. Why does my old .fetchmailrc file no
884 longer work?</a></h2>
886 <h3>If your file predates 5.8.9</h3>
888 <p>If you were using ETRN mode, change your <tt>smtphost</tt>
889 option to a <tt>fetchdomains</tt> option.</p>
891 <h3>If your file predates 5.8.3</h3>
893 <p>The 'via localhost' special case for use with ssh tunnelling is
894 gone. Use the %h feature of <tt>plugin</tt> instead.</p>
896 <h3>If your file predates 5.6.8</h3>
898 <p>In 5.6.8, the <tt>preauth</tt> keyword and option were changed
899 back to <tt>auth</tt>. The <tt>preauth</tt> synonym will still be
900 supported through a few more point releases.</p>
902 <h3>If your file predates 5.6.5</h3>
904 <p>The <tt>imap-gss</tt>, <tt>imap-k4</tt>, and <tt>imap-login</tt>
905 protocol types are gone. This is a result of a major re-factoring
906 of the authentication machinery; fetchmail can now use Kerberos V4
907 and GSSAPI not just with IMAP but with POP3 servers that have
908 RFC1734 support for the AUTH command.</p>
910 <p>When trying to identify you to an IMAP or POP mailserver,
911 fetchmail now first tries methods that don't require a password
912 (GSSAPI, KERBEROS_IV); then it looks for methods that mask your
913 password (CRAM-MD5, X-OTP); and only if it the server doesn't
914 support any of those will it ship your password en clair.</p>
916 <p>Setting the <tt>preauth</tt> option to any value other than
917 'password' will prevent from looking for a password in your
918 <tt>.netrc</tt> file or querying for it at startup time.</p>
920 <h3>If your file predates 5.1.0</h3>
922 <p>In 5.1.0, the <tt>auth</tt> keyword and option were changed to
923 <tt>preauth</tt>.</p>
925 <h3>If your file predates 4.5.5</h3>
927 <p>If the <code>dns</code> option is on (the default), you may need
928 to make sure that any hostname you specify (for mail hosts or for
929 an SMTP target) is a canonical fully-qualified hostname). In order
930 to avoid DNS overhead and complications, fetchmail no longer tries
931 to derive the fetchmail client machine's canonical DNS name at
934 <h3>If your file predates 4.0.6:</h3>
936 <p>Just after the '<code>via</code>' option was introduced, I
937 realized that the interactions between the '<code>via</code>',
938 '<code>aka</code>', and '<code>localdomains</code>' options were
939 out of control. Their behavior had become complex and confusing, so
940 much so that I was no longer sure I understood it myself. Users
941 were being unpleasantly surprised.</p>
943 <p>Rather than add more options or crock the code, I re-thought it.
944 The redesign simplified the code and made the options more
945 orthogonal, but may have broken some complex multidrop
948 <p>Any multidrop configurations that depended on the name just
949 after the '<code>poll</code>' or '<code>skip</code>' keyword being
950 still interpreted as a DNS name for address-matching purposes, even
951 in the presence of a '<code>via</code>' option, will break.</p>
953 <p>It is theoretically possible that other unusual configurations
954 (such as those using a non-FQDN poll name to generate Kerberos IV
955 tickets) might also break; the old behavior was sufficiently murky
956 that we can't be sure. If you think this has happened to you,
957 contact the maintainer.</p>
959 <h3>If your file predates 3.9.5:</h3>
961 <p>The '<code>remote</code>' keyword has been changed to
962 '<code>folder</code>'. If you try to use the old keyword, the
963 parser will utter a warning.</p>
965 <h3>If your file predates 3.9:</h3>
967 <p>It could be because you're using a .fetchmailrc that's written
968 in the old popclient syntax without an explicit
969 '<code>username</code>' keyword leading the first user entry
970 attached to a server entry.</p>
972 <p>This error can be triggered by having a user option such as
973 '<code>keep</code>' or '<code>fetchall</code>' before the first
974 explicit username. For example, if you write</p>
977 poll openmail protocol pop3
978 keep user "Hal DeVore" there is hdevore here
981 <p>the '<code>keep</code>' option will generate an entire user
982 entry with the default username (the name of fetchmail's invoking
985 <p>The popclient compatibility syntax was removed in 4.0. It
986 complicated the configuration file grammar and confused users.</p>
988 <h3>If your file predates 2.8:</h3>
990 <p>The '<code>interface</code>', '<code>monitor</code>' and
991 '<code>batchlimit</code>' options changed after 2.8.</p>
993 <p>They used to be global options with '<code>set</code>' syntax
994 like the batchlimit and logfile options. Now they're per-server
995 options, like '<code>protocol</code>'.</p>
997 <p>If you had something like</p>
1000 set interface = "sl0/10.0.2.15"
1003 <p>in your .fetchmailrc file, simply delete that line and insert
1004 'interface sl0/10.0.2.15' in the server options part of your
1005 'defaults' declaration.</p>
1007 <p>Do similarly for any '<code>monitor</code>' or
1008 '<code>batchlimit</code>' options.</p>
1011 <h2><a id="F2" name="F2">F2. The .fetchmailrc parser won't accept
1012 my all-numeric user name.</a></h2>
1014 <p>Either upgrade to a post-5.0.5 fetchmail or put string quotes
1017 <p>The configuration file parser in older fetchmail versions
1018 treated any all-numeric token as a number, which confused it when
1019 it was expecting a name. String quoting forces the token's
1022 <p>The lexical analyzer in 5.0.6 and beyond is smarter and assumes
1023 any token following "username" or "password" is a string.</p>
1026 <h2><a id="F3" name="F3">F3. The .fetchmailrc parser won't accept
1027 my host or username beginning with 'no'.</a></h2>
1029 <p>See <a href="#F2">F2</a>. You're caught in an unfortunate crack
1030 between the newer-style syntax for negated options ('no keep', 'no
1031 rewrite' etc.) and the older style run-on syntax ('nokeep',
1032 'norewrite' etc.).</p>
1034 <p>Upgrade to a 5.0.6 or later fetchmail, or put string quotes
1035 around your token.</p>
1038 <h2><a id="F4" name="F4">F4. I'm getting a 'parse error' message I
1039 don't understand.</a></h2>
1041 <p>The most common cause of mysterious parse errors is putting a
1042 server option after a user option. Check the manual page; you'll
1043 probably find that by moving one or more options closer to the
1044 'poll' keyword you can eliminate the problem.</p>
1046 <p>Yes, I know these ordering restrictions are hard to understand.
1047 Unfortunately, they're necessary in order to allow the 'defaults'
1048 feature to work.</p>
1051 <h2><a id="C1" name="C1">C1. Why do I need a .fetchmailrc when
1052 running as root on my own machine?</a></h2>
1054 <p>Ian T. Zimmerman <itz@rahul.net> asked:</p>
1056 <p>On the machine where I'm the only real user, I run fetchmail as
1057 root from a cron job, like this:</p>
1060 fetchmail -u "itz" -p POP3 -s bolero.rahul.net
1063 <p>This used to work as is (with no .fetchmailrc file in root's
1064 home directory) with the last version I had (1.7 or 1.8, I don't
1065 remember). But with 2.0, it RECPs all mail to the local root user,
1066 unless I create a .fetchmailrc in root's home directory
1070 skip bolero.rahul.net proto POP3
1074 <p>It won't work if the second line is just "<code>user
1075 itz</code>". This is silly.</p>
1077 <p>It seems fetchmail decides to RECP the 'default local user'
1078 (i.e. the uid running fetchmail) unless there are local aliases,
1079 and the 'default' aliases (itz->itz) don't count. They
1084 <p>No they shouldn't. I thought about this for a while, and I don't
1085 much like the conclusion I reached, but it's unavoidable. The
1086 problem is that fetchmail has no way to know, in general, that a
1087 local user 'itz' actually exists.</p>
1089 <p>"Ah!" you say, "Why doesn't it check the password file to see if
1090 the remote name matches a local one?" Well, there are two
1093 <p>One: it's not always possible. Suppose you have an SMTP host
1094 declared that's not the machine fetchmail is running on? You
1097 <p>Two: How do you know server itz and SMTP-host itz are the same
1098 person? They might not be, and fetchmail shouldn't assume they are
1099 unless local-itz can explicitly produce credentials to prove it
1100 (that is, the server-itz password in local-itz's .fetchmailrc
1103 <p>Once you start running down possible failure modes and thinking
1104 about ways to tinker with the mapping rules, you'll quickly find
1105 that all the alternatives to the present default are worse or
1106 unacceptably more complicated or both.</p>
1109 <h2><a id="C2" name="C2">C2. How can I arrange for a fetchmail
1110 daemon to get killed when I log out?</a></h2>
1112 <p>The easiest way to dispatch fetchmail on logout (which will work
1113 reliably only if you have just one login going at any time) is to
1114 arrange for the command 'fetchmail -q' to be called on logout.
1115 Under bash, you can arrange this by putting 'fetchmail -q' in the
1116 file '~/.bash_logout'. Most csh variants execute '~/.logout' on
1117 logout. For other shells, consult your shell manual page.</p>
1119 <p>Automatic startup/shutdown of fetchmail is a little harder to
1120 arrange if you may have multiple login sessions going. In the
1121 contrib subdirectory of the fetchmail distribution there is some
1122 shell code you can add to your .bash_login and .bash_logout
1123 profiles that will accomplish this. Thank James Laferriere
1124 <babydr@nwrain.net> for it.</p>
1126 <p>Some people start up and shut down fetchmail using the ppp-up
1127 and ppp-down scripts of pppd.</p>
1130 <h2><a id="C3" name="C3">C3. How do I know what interface and
1131 address to use with --interface?</a></h2>
1133 <p>This depends a lot on your local networking configuration (and
1134 right now you can't use it at all except under Linux and the newer
1135 BSDs). However, here are some important rules of thumb that can
1136 help. If they don't work, ask your local sysop or your Internet
1139 <p>First, you may not need to use --interface at all. If your
1140 machine only ever does SLIP or PPP to one provider, it's almost
1141 certainly by a point to point modem connection to your provider's
1142 local subnet that's pretty secure against snooping (unless someone
1143 can tap your phone or the provider's local subnet!). Under these
1144 circumstances, specifying an interface address is fairly
1147 <p>What the option is really for is sites that use more than one
1148 provider. Under these circumstances, typically one of your provider
1149 IP addresses is your mailserver (reachable fairly securely via the
1150 modem and provider's subnet) but the others might ship your packets
1151 (including your password) over unknown portions of the general
1152 Internet that could be vulnerable to snooping. What you'll use
1153 --interface for is to make sure your password only goes over the
1154 one secure link.</p>
1156 <p>To determine the device:</p>
1159 <li>If you're using a SLIP link, the correct device is probably
1162 <li>If you're using a PPP link, the correct device is probably
1165 <li>If you're using a direct connection over a local network such
1166 as an ethernet, use the command 'netstat -r' to look at your
1167 routing table. Try to match your mailserver name to a destination
1168 entry; if you don't see it in the first column, use the 'default'
1169 entry. The device name will be in the rightmost column.</li>
1172 <p>To determine the address and netmask:</p>
1175 <li>If you're talking to slirp, the correct address is probably
1176 10.0.2.15, with no netmask specified. (It's possible to configure
1177 slirp to present other addresses, but that's the default.)</li>
1179 <li>If you have a static IP address, run 'ifconfig <device>',
1180 where <device> is whichever one you've determined. Use the IP
1181 address given after "inet addr:". That is the IP address for your
1182 end of the link, and is what you need. You won't need to specify a
1185 <li>If you have a dynamic IP address, your connection IP will vary
1186 randomly over some given range (that is, some number of the least
1187 significant bits change from connection to connection). You need to
1188 declare an address with the variable bits zero and a complementary
1189 netmask that sets the range.</li>
1192 <p>To illustrate the rule for dynamic IP addresses, let's suppose
1193 you're hooked up via SLIP and your IP provider tells you that the
1194 dynamic address pool is 255 addresses ranging from 205.164.136.1 to
1195 205.164.136.255. Then</p>
1198 interface "sl0/205.164.136.0/255.255.255.0"
1201 <p>would work. To range over any value of the last two octets
1202 (65536 addresses) you would use</p>
1205 interface "sl0/205.164.0.0/255.255.0.0"
1209 <h2><a id="C4" name="C4">C4. How can I set up support for
1210 sendmail's anti-spam features?</a></h2>
1212 <p>This answer covers versions of sendmail from 8.9.3-20 (the
1213 version installed in Red Hat 6.2) upwards. If you have an older
1214 version, upgrade to sendmail 8.9.</p>
1216 <p>Stock sendmails can now do anti-spam exclusions based on a
1217 database of filter rules. The human-readable form of the database
1218 is at <tt>/etc/mail/access</tt>. The database itself is at
1219 <tt>/etc/mail/access.db</tt>.</p>
1221 <p>The table itself uses email addresses, domain names, and network
1222 numbers as keys. For example,</p>
1225 spammer@aol.com REJECT
1226 cyberspammer.com REJECT
1230 <p>would refuse mail from spammer@aol.com, any user from
1231 cyberspammer.com (or any host within the cyberspammer.com domain),
1232 and any host on the 192.168.212.* network. (This feature can be
1233 used to do other things as well; see the <a
1234 href="http://www.sendmail.org/m4/anti-spam.html">sendmail
1235 documentation</a> for details)</p>
1237 <p>To actually set up the database, run</p>
1240 makemap hash deny <deny
1243 <p>in /etc/mail.</p>
1245 <p>To test, send a message to your mailing address from that host
1246 and then pop off the message with fetchmail, using the -v argument.
1247 You can monitor the SMTP transaction, and when the FROM address is
1248 parsed, if sendmail sees that it is an address in spamlist,
1249 fetchmail will flush and delete it.</p>
1251 <p>Under no circumstances put your <strong>mailhost</strong> or
1252 <strong>any host you accept mail from</strong> using fetchmail into
1253 your reject file. You <strong>will</strong> lose mail if you do
1257 <h2><a id="C5" name="C5">C5. How can I poll some of my mailboxes
1258 more/less often than others?</a></h2>
1260 <p>Use the <cite>interval</cite> keyword on the ones that should be
1261 checked less often. For example, if you do a poll every 5 minutes,
1262 and want to poll some mailboxes every 5 minutes and some every 30
1263 minutes, use something like this:</p>
1266 poll mainsite.example.com proto pop3 user ....
1267 poll secondary.example.com proto pop3 interval 6 user ...
1270 <p>Then secondary.example.com will be polled every 6th time that
1271 mainsite.example.com is polled, which with a polling interval of
1272 every 5 minutes means that secondary.example.com will be polled
1273 every 30 minutes.</p>
1276 <h2><a id="C6" name="C6">Fetchmail works OK started up manually,
1277 but not from an init script.</a></h2>
1279 <p>Often, startup scripts have a different environment than an
1280 interactive login shell. For instance, $HOME might point to "/root"
1281 when you are logged in as root, but it might be either unset, or
1282 set to "/" when the startup scripts are running. That means
1283 fetchmail at startup can't find the .fetchmailrc.</p>
1285 <p>Pick a location (such as /etc/fetchmailrc) and use fetchmail's
1286 -f option to point fetchmail at it. That should solve the
1290 <h2><a id="C7" name="C7">C7. How can I forward mail to another
1293 <p>To forward mail to a host other than the one you are running
1294 fetchmail on, use the <code>smtphost</code> or
1295 <code>smtpname</code> option. See the manual page for details.</p>
1298 <h2><a id="T1" name="T1">T1. How can I use fetchmail with
1301 <p>For most sendmails, no special configuration is required. Eric
1302 Allman tells me that if <code>FEATURE(always_add_domain)</code> is
1303 included in sendmail's configuration, you can leave the
1304 <code>rewrite</code> option off.</p>
1306 <p>If your sendmail complains "sendmail does not relay", make
1307 sure your sendmail.cf file says <code>Cwlocalhost</code> so that
1308 sendmail recognizes 'localhost' as a name of its host.</p>
1310 <p>If you're mailing from another machine on your local network,
1311 also ensure that its IP address is listed in ip_allow or name in
1312 name_allow (usually in /etc/mail/)</p>
1314 <p>If you find that your sendmail doesn't like the address
1315 'FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail that
1316 fetchmail generates), you may have to set
1317 <code>FEATURE(accept_unqualified_senders)</code>.</p>
1319 <p>Günther Leber reports that Digital Unix sendmails won't
1320 work with fetchmail. The symptom is an error message "<code>553
1321 Local configuration error, hostname not recognized as
1322 local</code>". The problem is that fetchmail normally feeds
1323 sendmail with the client machine's host address in the MAIL FROM
1324 line. These sendmails think this means they're seeing the result of
1325 a mail loop and suppress the mail. You may be able to work around
1326 this by running in <code>--invisible</code> mode.</p>
1328 <p>If you want to support multidrop mode, and you can get access to
1329 your mailserver's sendmail.cf file, it's a good idea to add this
1333 H?l?Delivered-To: $h
1336 <p>This will cause the mailserver's sendmail to reliably write the
1337 appropriate envelope address into each message before fetchmail
1338 sees it, and tell fetchmail which header it is.  With this
1339 change, multidrop mode should work reliably even when the Received
1340 header omits the envelope address (which will typically be the case
1341 when the message has multiple recipients).  However it will
1342 still not distinguish the recipients, your only advantage is that
1343 no bounce will be sent if a message is BCC addressed to multiple
1344 users at your site.  To fix even that problem, you might want
1345 to try the following hack, which is however untested and quite
1349 H?J?Delivered-To: $u
1351 Mmdrop, P=/usr/bin/procmail, F=lsDFMqSPfhnu9J,
1352 S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP/HdrToSMTP,
1353 T=DNS/RFC822/X-Unix,
1354 A=procmail -Y -a $u -d $h
1357 <p>For both hacks, you have to declare '<code>envelope
1358 "Delivered-To:"</code>' on the fetchmail side, to put the virtual
1359 domain (e.g. 'domain.com') with RELAY permission into your access
1360 file and to add a line reading '<code>domain.com
1361 local:local-pop-user</code>' for the first and '<code>domain.com
1362 mdrop:local-pop-user</code>' for the second hack to your
1365 <p>You will notice that if the mail already has a Delivered-To
1366 header, sendmail will not add another.  Further, editing
1367 sendmail.cf directly is not very comfortable.  Solutions for
1368 both problems can be found in Peter 'Rattacresh' Backes' 'hybrid'
1369 patch against sendmail.  Have a look at it, you can find it in
1370 the contrib subdirectory.</p>
1372 <p>Feel free to try Martijn Lievaart's detailed recipe in the
1373 contrib subdirectory of the fetchmail source distribution, it
1374 attempts to realize multidrop mailboxes with an external
1377 <p>If for some reason you are invoking sendmail via the
1378 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
1379 don't forget to include the -i switch. Otherwise you will
1380 occasionally get mysterious delivery failures with a SIGPIPE as the
1381 sendmail instance dies. The problem is messages with a single dot
1382 at start of a text line.</p>
1385 <h2><a id="T2" name="T2">T2. How can I use fetchmail with
1388 <p>Turn on the <code>forcecr</code> option; qmail's listener mode
1389 doesn't like header or message lines terminated with bare
1392 <p>(This information is thanks to Robert de Bath
1393 <robert@mayday.cix.co.uk>.)</p>
1395 <p>If a mailhost is using the qmail package (see <a
1396 href="http://pobox.com/~djb/qmail.html">http://pobox.com/~djb/qmail.html</a>)
1397 then, providing the local hosts are also using qmail, it is
1398 possible to set up one fetchmail link to be reliably collect the
1399 mail for an entire domain.</p>
1401 <p>One of the basic features of qmail is the 'Delivered-To:'
1402 message header. Whenever qmail delivers a message to a local
1403 mailbox it puts the username and hostname of the envelope recipient
1404 on this line. The major reason for this is to prevent mail
1407 <p>To set up qmail to batch mail for a disconnected site the
1408 ISP-mailhost will have normally put that site in its 'virtualhosts'
1409 control file so it will add a prefix to all mail addresses for this
1410 site. This results in mail sent to
1411 'username@userhost.userdom.dom.com' having a 'Delivered-To:' line
1415 Delivered-To: mbox-userstr-username@userhost.userdom.dom.com
1418 <p>A single host maildrop will be slightly simpler:</p>
1421 Delivered-To: mbox-userstr-username@userhost.dom.com
1424 <p>The ISP can make the 'mbox-userstr-' prefix anything they choose
1425 but a string matching the user host name is likely.</p>
1427 <p>To use this line you must:</p>
1430 <li>Ensure the option 'envelope Delivered-To:' is in the fetchmail
1433 <li>Ensure you have a localdomains containing 'userdom.dom.com' or
1434 'userhost.dom.com' respectively.</li>
1437 <p>So far this reliably delivers messages to the correct machine of
1438 the local network, to deliver to the correct user the
1439 'mbox-userstr-' prefix must be stripped off of the user name. This
1440 can be done by setting up an alias within the qmail MTA on each
1441 local machine. Simply create a dot-qmail file called
1442 '.qmail-mbox-userstr-default' in the alias directory (normally
1443 /var/qmail/alias) with the contents:</p>
1446 | ../bin/qmail-inject -a -f"$SENDER" "${LOCAL#mbox-userstr-}@$HOST"
1449 <p>Note this <em>does</em> require a modern /bin/sh.</p>
1451 <p>Peter Wilson adds:</p>
1453 <p>"My ISP uses "alias-unzzippedcom-" as the prefix, which means
1454 that I need to name my file ".qmail-unzzippedcom-default". This is
1455 due to qmail's assumption that a message sent to user-xyz is
1456 handled by the file ~user/.qmail-xyz (or
1457 ~user/.qmail-default)."</p>
1459 <p>Luca Olivetti adds:</p>
1461 <p>If you aren't using qmail locally, or you don't want to set up
1462 the alias mechanism described above, you can use the option
1463 '<code>qvirtual "mbox-userstr-"</code>' in your fetchmail config
1464 file to strip the prefix from the local user name.</p>
1467 <h2><a id="T3" name="T3">T3. How can I use fetchmail with
1470 <p>If you have <code>rewrite</code> on:</p>
1472 <p>There is an RFC1123 requirement that MAIL FROM and RCPT TO
1473 addresses you pass to it have to be canonical (e.g. with a fully
1474 qualified hostname part). Therefore fetchmail tries to pass fully
1475 qualified RCPT TO addresses. But exim does not by default accept
1476 'localhost' as a fully qualified domain. This can be fixed.</p>
1478 <p>In exim.conf, add 'localhost' to your local_domains declaration
1479 if it's not already present. For example, the author's site at
1480 thyrsus.com would have a line reading:</p>
1483 local_domains = thyrsus.com:localhost
1486 <p>If you have <code>rewrite</code> off:</p>
1488 <p>MAIL FROM is a potential problem if the MTAs upstream from your
1489 fetchmail don't necessarily pass canonicalized From and Return-Path
1490 addresses, and fetchmail's <code>rewrite</code> option is off. The
1491 specific case where this has come up involves bounce messages
1492 generated by sendmail on your mailer host, which have the
1493 (un-canonicalized) origin address MAILER-DAEMON.</p>
1495 <p>The right way to fix this is to enable the <code>rewrite</code>
1496 option and have fetchmail canonicalize From and Return-Path
1497 addresses with the mailserver hostname before exim sees them. This
1498 option is enabled by default, so it won't be off unless you turned
1501 <p>If you must run with <code>rewrite</code> off, there is a switch
1502 in exim's configuration files that allows it to accept domainless
1503 MAIL FROM addresses; you will have to flip it by putting the
1507 sender_unqualified_hosts = localhost
1510 <p>in the main section of the exim configuration file. Note that
1511 this will result in such messages having an incorrect domain name
1512 attached to their return address (your SMTP listener's hostname
1513 rather than that of the remote mail server).</p>
1516 <h2><a id="T4" name="T4">T4. How can I use fetchmail with
1519 <p>Smail 3.2 is very nearly plug-compatible with sendmail, and may
1520 work fine out of the box.</p>
1522 <p>We have one report that when processing multiple messages from a
1523 single fetchmail session, smail sometimes delivers them in an order
1524 other than received-date order. This can be annoying because it
1525 scrambles conversational threads. This is not fetchmail's problem,
1526 it is an smail 'feature' and has been reported to the maintainers
1529 <p>Very recent smail versions require an
1530 <code>-smtp_hello_verify</code> option in the smail config file.
1531 This overrides smail's check to see that the HELO address is
1532 actually that of the client machine, which is never going to be the
1533 case when fetchmail is in the picture. According to RFC1123 an SMTP
1534 listener <em>must</em> allow this mismatch, so smail's new behavior
1535 (introduced sometime between 3.2.0.90 and 3.2.0.95) is a bug.</p>
1537 <p>You may also need to say
1538 <code>-smtp_hello_broken_allow=127.0.0.1</code> in order for smail
1539 to accept the "localhost" that fetchmail normally appends to
1540 recipient addresses.</p>
1543 <h2><a id="T5" name="T5">T5. How can I use fetchmail with SCO's
1546 <p>MMDF itself is difficult to configure, but it turns out that
1547 connecting fetchmail to MMDF's SMTP channel isn't that hard. You
1549 href="http://www.aplawrence.com/Unixart/uucptofetch.html">MMDF
1550 recipe</a> that describes replacing a UUCP link with fetchmail
1554 <h2><a id="T6" name="T6">T6. How can I use fetchmail with Lotus
1557 <p>The Lotus Notes SMTP gateway tries to deduce when it should
1558 convert \n to \r\n, but its rules are not the intuitive and
1559 correct-for-RFC822 ones. Use 'forcecr'.</p>
1562 <h2><a id="T7" name="T7">T7. How can I use fetchmail with Courier
1565 <p>The courier mta doesn't like RCPT addresses that look like
1566 <code>someone@localhost</code>. Work around this with an
1567 <code>smtphost</code> or <code>smtpaddress</code>.</p>
1570 <h2><a name="T8">T8. How can I use fetchmail with vbmailshield?</a></h2>
1572 <p>vbmailshield's SMTP interpreter is broken. It doesn't understand RSET.</p>
1574 <p>As a workaround, you can set batchlimit to 1 so RSET is never used.</p>
1577 <h2><a id="S1" name="S1">S1. How can I use fetchmail with
1580 <p>Qualcomm's qpopper is probably the best-of-breed among POP3
1581 servers, and is very widely deployed. Nevertheless, it has some
1582 problems which fetchmail exposes. We recommend using <a
1583 href="#G8">IMAP</a> instead if at all possible. If you must talk to
1584 qpopper, here are some problems to be aware of:</p>
1586 <h3>Problems with retrieving large messages from qpopper 2.53</h3>
1589 href="mailto:tony@atn.com.hk"><tony@atn.com.hk></a> reports
1590 that there is a bad intercation between fetchmail and qpopper 2.5.3
1591 under Red Hat Linux versions 5.0 to 5.2, kernels 2.0.34 to 2.0.35.
1592 When fetching very large messages (over 700K) from 2.5.3, fetchmail
1593 will hang with a socket error.</p>
1595 <p>This is probably not a fetchmail bug, but rather a symptom of
1596 some problem in the networking stack that qpopper's transmission
1597 pattern is tickling, as fetchpop (another Linux POP client) also
1598 displays the hang but Netscape running under Win95 does not. The
1599 problem can also be banished by <a
1600 href="http://www.eudora.com/freeware/qpop.html">upgrading to
1601 qpopper 3.0b1</a>.</p>
1603 <h3>Bad interaction with fetchmail 4.4.2 to 4.4.7</h3>
1605 <p>Versions of fetchmail from 4.4.2 through 4.4.7 had a bad
1606 interaction with Eudora qpopper versions 2.3 and later. See <a
1607 href="#X5">X5</a> for details. The solution is to upgrade your
1611 <h2><a id="S2" name="S2">S2. How can I use fetchmail with Microsoft
1614 <p>It's been reliably reported that Exchange 2000's POP3 support is
1615 so broken that it's unusable. One symptom is that messages without
1616 a terminating newline get the POP3 message termination dot emitted
1617 -- you guessed it -- right after the last character of the message,
1618 with no terminating newline added. This will hang fetchmail or any
1619 other RFC-compliant server. IMAP is alleged to work OK, though.</p>
1621 <p>Older versions of Exchange are semi-usable. They randomly drop
1622 attachments on the floor, though. Microsoft acknowledges this
1623 as a known bug and apparently has no plans to fix it.</p>
1625 <p>Fetchmail using IMAP supports the proprietary NTLM mode used
1626 with M$ Exchange servers. To enable this, configure fetchmail with
1627 the --enable-NTLM option and recompile it. Specify a user option
1628 value that looks like 'user@domain': the part to the left of the @
1629 will be passed as the username and the part to the right as the
1632 <p>M$ Exchange violates the POP3 and IMAP RFCs. Its LIST command
1633 does not reveal the real sizes of mail in the pop mailbox, but the
1634 sizes of the compressed versions in the exchange mail database
1635 (thanks to Arjan De Vet and Guido Van Rooij for alerting us to this
1638 <p>Fetchmail works with M$ Exchange, despite this brain damage. Two
1639 features are compromised. One is that the --limit option will not
1640 work right (it will check against compressed and not actual sizes).
1641 The other is that a too-small SIZE argument may be passed to your
1642 ESMTP listener, assuming you're using one (this should not be a
1643 problem unless the actual size of the message is above the
1644 listener's configured length limit).</p>
1646 <p>Somewhat belatedly, I've learned that there's supposed to be a
1647 registry bit that can fix this breakage:</p>
1650 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1651 System\Pop3 Compatibility
1654 <p>This is a bitmask that controls the variations from the standard
1655 protocol. The bits defined are:</p>
1658 <dt>0x00000001:</dt>
1660 <dd>Report exact message sizes for the LIST command</dd>
1662 <dt>0x00000002:</dt>
1664 <dd>Allow arbitrary linear whitespace between commands and
1667 <dt>0x00000004:</dt>
1669 <dd>Enable the LAST command</dd>
1671 <dt>0x00000008:</dt>
1673 <dd>Allow an empty PASS command (needed for users with blank
1674 passwords, but illegal in the protocol)</dd>
1676 <dt>0x00000010:</dt>
1678 <dd>Relax the length restrictions for arguments to commands
1679 (protocol requires 40, but some user names may be longer than
1682 <dt>0x00000020:</dt>
1684 <dd>Allow spaces in the argument to the USER command.</dd>
1687 <p>There's another one that may be useful to know about:</p>
1690 KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1691 System\Pop3 Performance
1695 <dt>0x00000001:</dt>
1697 <dd>Render messages to a temporary stream instead of sending
1698 directly from the database (should always be on)</dd>
1700 <dt>0x00000002: Flag unrenderable messages (instead of just failing
1701 commands) (should only be on if you are seeing the problems
1702 reported in KB Q168109)</dt>
1704 <dt>0x00000004:</dt>
1706 <dd>Return from the QUIT command before all messages have been
1710 <p>The Microsoft pod-person who revealed this information to me
1711 admitted that he couldn't find it anywhere in their public
1714 <p>Another specific problem we have seen with Exchange servers has
1715 as its symptom a response to LOGIN that says "NO Ambiguous Alias".
1716 Grant Edwards writes:</p>
1718 <p>This means that Exchange Server is too f*&#ing stupid to
1719 figure out which mailbox belongs to you. Instead of actually
1720 keeping track of which inbox belongs to which user, it uses some
1721 half-witted, guess-o-matic heuristic to try to guess your mailbox
1722 name from your username.</p>
1724 <p>In your case it doesn't work because your username maps to more
1725 than one mailbox. For some people it doesn't work because their
1726 username maps to zero mailboxes. This is yet another inept, lame,
1727 almost criminally negligent design decision from our friends in
1730 <p>You've got several options:</p>
1733 <li>Get your administrator to configure the server so that
1734 usernames and mailbox names are the same.</li>
1736 <li>Get your administrator to add an alias that maps your username
1737 explicitly to your mailbox name.</li>
1740 <p>But, the best option involves a tactical nuclear weapon (an old
1741 ASROC will do), pissing off a lot people who live downwind from
1742 Redmond, and your choice of any Linux, NetBSD, FreeBSD, or Solaris
1746 <h2><a id="S3" name="S3">S3. How can I use fetchmail with HP
1749 <p>No special configuration is required, but OpenMail versions
1750 prior to 6.0 have an annoying bug similar to the big one in <a
1751 href="#S2">Microsoft Exchange</a>. The message sizes it gives in
1752 the LIST are rounded to the nearest 1024 bytes. It also has a nasty
1753 habit of discarding headers it doesn't recognize, such as X- and
1754 Resent- headers.</p>
1756 <p>As with M$ Exchange, the only real fix for these problems is to
1757 get a POP (or preferably IMAP) server that isn't brain-dead.
1758 OpenMail's project manager claims these bugs have been fixed in
1761 <p>We've had a more recent report (December 2001) that the TOP
1762 command fails, returning only one line regrardless of its argument,
1763 on something identifying itself as "OpenMail POP3 interface".</p>
1766 <h2><a id="S4" name="S4">S4. How can I use fetchmail with Novell GroupWise?</a></h2>
1768 <p>The Novell GroupWise IMAP server would be better named
1769 GroupFoolish; it is (according to the designer of IMAP) unusably
1770 broken. Among other things, it doesn't include a required content
1771 length in its BODY[TEXT] response.</p>
1773 <p>Fetchmail works around this problem, but we strongly recommend
1774 voting with your dollars for a server that isn't brain-dead. If you
1775 stick with code as shoddy as GroupWise seems to be, you will
1776 probably pay for it with other problems.</p>
1779 <h2><a id="S5" name="S5">S5. How can I use fetchmail with
1780 InterChange?</a></h2>
1782 <p>You can't. At least not if you want to be able to see
1783 attachments. InterChange has a bug similar to the MailMax server;
1784 it reports the message length with attachments but doesn't download
1785 them on TOP or RETR.</p>
1787 <p>On Jan 9 2001, the people at InfiniteMail sent me mail informing
1788 me that their new 3.61.08 release of InterChange fixes this
1789 problem. I don't have any reports one way or the other yet.</p>
1792 <h2><a id="S6" name="S6">S6. How can I use fetchmail with MailMax?</a></h2>
1794 <p>You can't. At least not if you want to be able to see
1795 attachments. MailMax has a bug; it reports the message length with
1796 attachments but doesn't download them on TOP or RETR.</p>
1798 <p>Also, we're told that TOP sometimes fails to retrieve the entire
1799 message even when enough lines have been specified. The MailMax
1800 developers have acknowledged this bug as of 4 May 2000, but there
1801 is no fix yet. If you must use this server, force RETR with the
1802 <tt>fetchall</tt> option.</p>
1805 <h2><a id="S7" name="S7">S7. How can I use fetchmail with FTGate?</a></h2>
1807 <p>The FTGate V2 server (and possibly older versions as well) has a
1808 weird bug. It answers OK twice to a TOP request! Use the
1809 <code>fetchall</code> option to force use of RETR and work around
1813 <h2><a id="I1" name="I1">I1. How can I use fetchmail with CompuServe RPA?</a></h2>
1815 <p>First, make sure your fetchmail has the RPA support compiled in.
1816 Stock fetchmail binaries (such as you might get from an RPM) don't.
1817 You can check this by looking at the output of <code>fetchmail
1818 -V</code>; if you see the string "+RPA" after the version ID you're
1819 good to go, otherwise you'll have to build your own from sources
1820 (see the INSTALL file in the source distribution for
1823 <p>Give your CompuServe pass-phrase in lower case as your password.
1824 Add '@compuserve.com' to your user ID so that it looks like 'user
1825 <UserID>@compuserve.com', where <UserID> can be either
1826 your numerical userID or your E-mail nickname. An RPA-enabled
1827 fetchmail will automatically check for csi.com in the POP server's
1828 greeting line. If that's found, and your user ID ends with
1829 '@compuserve.com', it will query the server to see if it is
1830 RPA-capable, and if so do an RPA transaction rather than a
1831 plain-text password handshake.</p>
1833 <p><strong>Warning:</strong> the debug (-v -v) output of fetchmail
1834 will show your pass-phrase in Unicode!</p>
1836 <p>These two .fetchmailrc entries show the difference between an
1837 RPA and non-RPA configuration:</p>
1840 # This version will use RPA
1841 poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1842 user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
1843 is LOCAL_USER here options fetchall stripcr
1845 # This version will not use RPA
1846 poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1847 user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
1848 is LOCAL_USER here options fetchall stripcr
1852 <h2><a id="I2" name="I2">I2. How can I use fetchmail with Demon
1853 Internet's SDPS?</a></h2>
1855 <h3>Single-drop mode</h3>
1857 <p>You can get fetchmail to download the email for just one user
1858 from Demon Internet's POP3 server by giving it a username
1859 consisting of your Demon user name followed by your account name,
1860 with an at-sign between them.</p>
1862 <p>For example, to download email for the user
1863 <philh@vision25.demon.co.uk>, you could use the following
1864 .fetchmailrc file:</p>
1867 set postmaster "philh"
1868 poll pop3.demon.co.uk with protocol POP3:
1869 user "philh@vision25" is philh
1872 <h3>Multi-drop mode</h3>
1874 <p>Demon Internet's SDPS service is an implementation of POP3. All
1875 messages have a Received: header added when they enter the
1876 maildrop, like this:</p>
1879 Received: from punt-1.mail.demon.net by mailstore for fred@xyz.demon.co.uk
1880 id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
1883 <p>To enable multi-drop mode you need to tell fetchmail that
1884 'mailstore' is the name of the host which accepted the mail, and
1885 let it know the hostname part(s) of your E-mail address. The
1886 following example assumes that your hostname is xyz.demon.co.uk,
1887 and that you have also bought "mail forwarding" for the domain
1888 my-company.co.uk (in which case your MTA must also be configured to
1889 accept mail sent to user@my-company.co.uk)</p>
1892 poll pop3.demon.co.uk proto pop3 aka mailstore no dns:
1893 localdomains xyz.demon.co.uk my-company.co.uk
1897 <p>Note that Demon may delete mail on the server which is more than
1898 30 days old; see their <a
1899 href="http://www.demon.net/helpdesk/products/mail/sdps-tech.shtml">POP3
1900 page</a> for details.</p>
1902 <h3>The SDPS extension</h3>
1904 <p>There's a different way to do multidrop. It's not necessary on
1905 Demon Internet, since fetchmail can parse Received addresses, but
1906 the person who implemented this didn't know that. It may be useful
1907 if Demon Internet ever changes mail transports.</p>
1909 <p>SDPS includes a non-standard extension for retrieving the
1910 envelope of a message (*ENV), which fetchmail optionally supports
1911 if compiled with the --enable-SDPS option. If you have it, the
1912 first line of the fetchmail -V response will include the string
1915 <p>Once you have SDPS compiled in, fetchmail in POP3 mode will
1916 automatically detect when it's talking to a Demon Internet host in
1917 multidrop mode, and use the *ENV extension to get an envelope To
1920 <p>The autodetection works by looking at the hostname in the POP3
1921 greeting line; if you're accessing Demon Internet through a proxy
1922 it may fail. To force SDPS mode, pick "sdps" as your protocol.</p>
1925 <h2><a id="I3" name="I3">I3. How can I use fetchmail with usa.net's
1928 <p>Enable '<code>fetchall</code>'. A user reports that the 2.2
1929 version of USA.NET's POP server reports that you must use the
1930 '<code>fetchall</code>' option to make sure that all of the mail is
1931 retrieved, otherwise some may be left on the server. This is almost
1932 certainly a server bug.</p>
1934 <p>The usa.net servers (at least in their 2.2 version, June 1998)
1935 don't handle the TOP command properly, either. Regardless of the
1936 argument you give it, they retrieve only about 10 lines of the
1937 message. Fetchmail normally uses TOP for message retrieval in order
1938 to avoid marking messages seen, but '<code>fetchall</code>' forces
1939 it to use RETR instead.</p>
1941 <p>Also, we're told USA.NET adds a ton of hops to your messages.
1942 You may need to raise the MaxHopCount parameter in your sendmail.cf
1943 to avoid having fetched mail rejected.</p>
1945 <p>(Note: Other failure modes have been reported on usa.net's
1946 servers. They seem to be chronically flaky. We recommend finding
1947 another provider.)</p>
1950 <h2><a id="I4" name="I4">I4. How can I use fetchmail with geocities
1951 POP3 servers?</a></h2>
1953 <p>Nathan Cutler reports that the the mail.geocities.com POP3
1954 servers fail to include the first Received line of the message in
1955 the send to fetchmail. This can solve problems if your MUA
1956 interprets Received continuations as body lines and doesn't parse
1957 any of the following headers.</p>
1959 <p>Workaround is to use "mda" keyword or "-mda" switch:</p>
1962 mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
1965 <p>Replace \t with exactly one tabulation character.</p>
1967 <p>You should also consider using "fetchall" option because
1968 Geocities' servers sometimes think that the first 45 messages have
1969 already been read.</p>
1971 <p>Fix: Get an email provider that doesn't suck. The pop-up ads on
1972 Geocities are lame, you should boycott them anyway.</p>
1975 <h2><a id="I5" name="I5">I5. How can I use fetchmail with Hotmail or Lycos Webmail?</a></h2>
1977 <p>You can't directly. But you can use fetchmail with hotmail or lycos
1978 webmail with the help of the <a
1979 href='http://people.freenet.de/courierdave/'>HotWayDaemon</a>
1980 daemon. You don't even need to install hotwayd as a daemon in
1981 <samp>inetd.conf</samp> but can use it as a plugin. Your
1982 configuration should look like this:</p>
1985 poll localhost protocol pop3 tracepolls
1986 plugin "/usr/local/sbin/hotwayd -l 0 -p yourproxy:yourproxyport"
1987 username "youremail@hotmail.com" password "yourpassword"
1991 <p>As a second option you may consider using <a
1992 href="http://linux.cudeso.be/linuxdoc/gotmail.php">gotmail</a>.</p>
1995 <h2><a id="I6" name="I6">I6. How can I use fetchmail with MSN?</a></h2>
1997 <p>You can't. MSN uses something that looks like POP3, except the
1998 authentication part is nonstandard. And of course they don't
1999 document it, so nobody but their Windows clients can speak it.</p>
2001 <p>This is a customer lock-in tactic; we recommend boycotting MSN
2002 as the only appropriate response.</p>
2004 <p>As of 5.0.8, we have support for the client side of NTLM
2005 authentication. It's possible this may enable fetchmail to talk to
2006 MSN; if so, somebody should report it so this FAQ can be
2010 <h2><a id="I7" name="I7">I7. How can I use fetchmail with SpryNet?</a></h2>
2012 <p>The SpryNet POP3 servers mark a message queried with TOP as
2013 seen. This means that if your connection drops in mid-message, it
2014 may end up invisibly stuck on your mail spool. Use the
2015 <code>fetchall</code> flag to ensure that it's recovered on the
2019 <h2><a id="I8" name="I8">I8. How can I use fetchmail with comcast.net?</a></h2>
2021 <p>Stock fetchmail will work with a comcast.net server...<em>but</em>
2022 the Maillennium POP3 server comcat uses seems to have an 80K limit on
2023 the length of downloaded messages if you use POP3 TOP to retrieve.
2024 Anything larger is silently truncated. Don't mistake this for a
2025 fetchmail bug. (Reported July 2003.)</p>
2027 <p>Workaround: use the <tt>fetchall</tt> option.</p>
2030 <h2><a id="K1" name="K1">K1. How can I use fetchmail with SOCKS?</a></h2>
2032 <p>Giuseppe Guerini added a --with-socks option that supports
2033 linking with socks library. If you specify the value of this option
2034 as "yes", the configure script will try to find the Rconnect
2035 library and set the makefile up to link it. You can also specify a
2036 directory containing the Rconnect library.</p>
2038 <p>Alan Schmitt has added a similar --with-socks5 option that may
2039 work better if you have a recent version of the SOCKS library.</p>
2042 <h2><a id="K2" name="K2">K2. How can I use fetchmail with IPv6 and
2045 <p>To use fetchmail with IPv6, you need a system that supports
2046 IPv6, the "Basic Socket Interface Extensions for IPv6" (RFC 2133).
2049 <p>The NRL IPv6+IPsec software distribution can be obtained from:
2051 href="http://web.mit.edu/network/isakmp">http://web.mit.edu/network/isakmp</a></p>
2053 <p>More information on using IPv6 with Linux can be obtained
2058 href="http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html">
2059 http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html</a></li>
2063 <h2><a id="K3" name="K3">K3. How can I get fetchmail to work with
2066 <p>Use the <tt>plugin</tt> option. This is dead simple with
2070 plugin "ssh %h /usr/sbin/imapd"
2073 <p>You may have to use a different absolute pathname, whatever the
2074 location of imapd on your mailserver is. This option tells
2075 fetchmail that instead of opening a connection on the server's port
2076 143 and doing standard IMAP authentication, fetchmail should ssh to
2077 the server and run imapd, using the more secure ssh authentication
2078 (as well as getting ssh's end-to-end encryption). Most IMAP daemons
2079 will detect that they've been called from the command line and
2080 assume the connection is preauthenticated.</p>
2082 <p>POP3 daemons aren't quite as smart. They won't know they are
2083 preauthenticated in this mode, so you'll actually have to ship your
2084 password. It will be under ssh encryption, though, so that
2085 shouldn't be a problem.</p>
2088 <h2><a id="K4" name="K4">K4. What do I have to do to use the
2089 IMAP-GSS protocol?</a></h2>
2091 <p>Fetchmail can use RFC1731 GSSAPI authorization to safely
2092 identify you to your IMAP server, as long as you can share Kerberos
2093 V credentials with your mail host and you have a GSSAPI-capable
2094 IMAP server. UW-IMAP (available via FTP at <a
2095 href="ftp://ftp.cac.washington.edu/mail/">ftp.cac.washington.edu</a>)
2096 is the only one I'm aware of and the one I recommend anyway for
2097 other reasons. You'll need version 4.1-FINAL or greater though, and
2098 it has to have GSS support compiled in.</p>
2100 <p>Neither UW-IMAP nor fetchmail compile in support for GSS by
2101 default, since it requires libraries from the Kerberos V
2102 distribution (available via FTP at <a
2103 href="ftp://athena-dist.mit.edu/pub/ATHENA/kerberos">athena-dist.mit.edu</a>).
2104 If you have these, compiling in GSS support is simple: add a
2105 <code>--with-gssapi=[/path/to/krb5/root]</code> option to
2106 configure. For instance, I have all of my Kerberos V libraries
2107 installed under /usr/krb5 so I run <code>configure
2108 --with-gssapi=/usr/krb5</code></p>
2110 <p>Setting up Kerberos V authentication is beyond the scope of this
2111 FAQ (you may find Jim Rome's paper <a
2112 href="http://www.ornl.gov/~jar/HowToKerb.html">How to Kerberize
2113 your site</a> helpful), but you'll at least need to add a
2114 credential for imap/[mailhost] to the keytab of the mail server
2115 (IMAP doesn't just use the host key). Then you'll need to have your
2116 credentials ready on your machine (cf. kinit).</p>
2118 <p>After that things are very simple. Set your protocol to imap-gss
2119 in your .fetchmailrc, and omit the password, since imap-gss doesn't
2120 need one. You can specify a username if you want, but this is only
2121 useful if your mailbox belongs to a username different from your
2122 Kerberos principal.</p>
2124 <p>Now you don't have to worry about your password appearing in
2125 cleartext in your .fetchmailrc, or across the network.</p>
2128 <h2><a id="K5" name="K5">K5. How can I use fetchmail with
2131 <p>You'll need to have the <a
2132 href="http://www.openssl.org/">OpenSSL</a> libraries installed.
2133 Configure with --with-ssl. If you have the OpenSSL libraries
2134 installed in the default location (/usr/local/ssl) ths will
2135 suffice. If you have them installed in a non-default location,
2136 you'll need to specify it as an argument to --with-ssl after an
2139 <p>Note that there is a known bug in the implementation of SSL_peek
2140 under OpenSSL versions 0.9.5 and older that fetchmail occasionally
2141 tripped over, causing hangs. It is recommended that you install
2144 <p>Fetchmail binaries built this way support <code>ssl</code>,
2145 <code>sslkey</code>, and <code>sslcert</code> options that control
2146 SSL encryption. You will need to have an SSL-enabled mailserver to
2147 use these options. See the manual page for details and some words
2148 of care on the limited security provided.</p>
2150 <p>If your open OpenSSL session dies with a message that complains
2151 "PRNG not seeded", update or improve your operating system. This
2152 means that the OpenSSL library on your machine has been unable to
2153 locate a source of random bits from which to seed its random-number
2154 generator; normally these come from the <tt>/dev/urandom</tt>, and
2155 this message probably means your OS doesn't have that device.</p>
2157 <p>An interactive program could seed the random number generator
2158 from keystroke timings or some other form of user input. Because
2159 fetchmail is primarily designed to run forever as a background
2160 daemon, that option is not available in this case.</p>
2162 <p>If you don't have the libraries installed, but do have the
2163 OpenSSL utility toolkit, something like this may work:</p>
2166 poll MYSERVER port 993 plugin "openssl s_client -connect %h:%p"
2167 protocol imap username MYUSERNAME password MYPASSWORD
2170 <p>You should note that SSL is only secure against a "man-in-the-middle"
2171 attack if the client is able to verify that the peer's public key is the
2172 correct one, and has not been substituted by an attacker. fetchmail can do
2173 this in one of two ways: by verifying the SSL certificate, or by checking
2174 the fingerprint of the peer's public key.</p>
2176 <p>There are three parts to SSL certificate verification: checking that the
2177 domain name in the certificate matches the hostname you asked to connect to;
2178 checking that the certificate expiry date has not passed; and checking that
2179 the certificate has been signed by a known Certificate Authority (CA). This
2180 last step takes some preparation, as you need to install the root
2181 certificates of all the CA's which you might come across.</p>
2183 <p>The easiest way to do this is using the root CA keys supplied in the
2184 OpenSSL distribution, which means you need to download and unpack the
2185 source tarball from www.openssl.org. Once you have done that:</p>
2188 <li><code>mkdir /etc/ssl/certs</code></li>
2189 <li>in the openssl-x.x.x/certs directory: <code>cp *.pem /etc/ssl/certs/</code></li>
2190 <li>in the openssl-x.x.x/tools directory: edit c_rehash and set
2191 <code>$dir="/etc/ssl"</code></li>
2192 <li>run "perl c_rehash". This generates a number of symlinks within the
2193 /etc/ssl/certs/ directory</li>
2196 <p>Now in .fetchmailrc, set option sslcertpath to point to this
2200 poll pop3.example.com proto pop3 uidl no dns
2201 user foobar@example.com password xyzzy is foobar ssl sslcertpath /etc/ssl/certs
2204 <p>If the server certificate has not been signed by a known CA (e.g. it is a
2205 self-signed certificate), then this certificate validation will always
2208 <p>Certificate verification is always attempted. If it fails, by default a
2209 warning is printed but the connection carries on (which means you are not
2210 protected against attack). If your server's certificate has been properly
2211 set up and verifies correctly, then add the "sslcertck" option to enforce
2212 validation. If your server doesn't have a valid certificate though (e.g. it
2213 has a self-signed certificate) then it will never verify, and the only way
2214 you can protect yourself is by checking the fingerprint.</p>
2216 <p>To check the peer fingerprint: first use fetchmail -v once to connect to
2217 the host, at a time when you are pretty sure that there is no attack in
2218 progress (e.g. you are not traversing any untrusted network to reach the
2219 server). Make a note of the fingerprint shown. Now embed this in your
2220 .fetchmailrc using the sslfingerprint option: e.g.</p>
2223 poll pop3.example.com proto pop3 uidl no dns
2224 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"
2227 <p>When you next connect, the public key presented by the server will be
2228 verified against the fingerprint given. If it's different, it may mean that
2229 a man-in-the-middle attack is in progress - or it might just mean that the
2230 server changed its key. It's up to you to determine which has happened.</p>
2233 <h2><a id="K6" name="K6">K6. How can I tell fetchmail not to use TLS
2234 if the server advertises it?</a></h2>
2236 <p>Some servers advertise STLS (POP3) or STARTTLS (IMAP), and fetchmail
2237 will automatically attempt TLS negotiation if SSL was enabled at compile
2238 time. This can however cause problems if the upstream didn't configure
2239 his certificates properly.</p>
2241 <p>In order to prevent fetchmail from trying TLS (STLS, STARTTLS)
2242 negotiation, add this option:</p>
2244 <pre>sslproto ssl23</pre>
2246 <p>This restricts fetchmail's SSL/TLS protocol choice from the default
2247 "SSLv2, SSLv3, TLSv1" to the two SSL variants, disabling TLSv1. Note
2248 however that this causes the connection to be unencrypted unless an
2249 encrypting "plugin" is used or SSL is requested explicitly.</p>
2252 <h2><a id="R1" name="R1">R1. Fetchmail isn't working, and -v shows
2253 'SMTP connect failed' messages.</a></h2>
2255 <p>Fetchmail itself is probably working, but your SMTP port 25
2256 listener is down or inaccessible.</p>
2258 <p>The first thing to check is if you can telnet to port 25 on your
2259 smtp host (which is normally 'localhost' unless you've specified an
2260 smtp option in your .fetchmailrc or on the command line) and get a
2261 greeting line from the listener. If the SMTP host is inaccessible
2262 or the listener is down, fix that first.</p>
2264 <p>In Red Hat Linux 6.x, SMTP is disabled by default. To fix this,
2265 set "DAEMON=yes" in your /etc/sysconfig/sendmail file, then restart
2266 sendmail by running "/sbin/service sendmail restart".</p>
2268 <p>If the listener seems to be up when you test with telnet, the
2269 most benign and typical problem is that the listener had a
2270 momentary seizure due to resource exhaustion while fetchmail was
2271 polling it -- process table full or some other problem that stopped
2272 the listener process from forking. If your SMTP host is not
2273 'localhost' or something else in /etc/hosts, the fetchmail glitch
2274 could also have been caused by transient nameserver failure.</p>
2276 <p>Try running fetchmail -v again; if it succeeds, you had one of
2277 these kinds of transient glitch. You can ignore these hiccups,
2278 because a future fetchmail run will get the mail through.</p>
2280 <p>If the listener tests up, but you have chronic failures trying
2281 to connect to it anyway, your problem is more serious. One way to
2282 work around chronic SMTP connect problems is to use --mda. But this
2283 only attacks the symptom; you may have a DNS or TCP routing
2284 problem. You should really try to figure out what's going on
2285 underneath before it bites you some other way.</p>
2287 <p>We have one report (from toby@eskimo.com) that you can sometimes
2288 solve such problems by doing an <code>smtp</code> declaration with
2289 an IP address that your routing table maps to something other than
2290 the loopback device (he used ppp0).</p>
2292 <p>We also have a report that this error can be caused by having an
2293 /etc/hosts file that associates your client host name with more
2294 than one IP address.</p>
2296 <p>It's also possible that your DNS configuration isn't looking at
2297 <code>/etc/hosts</code> at all. If you're using libc5, look at
2298 <code>/etc/resolv.conf</code>; it should say something like:</p>
2304 <p>so your <code>/etc/hosts</code> file is checked first. If you're
2305 running GNU libc6, check your <code>/etc/nsswitch.conf</code> file.
2306 Make sure it says something like</p>
2312 <p>again, in order to make sure <code>/etc/hosts</code> is seen
2315 <p>If you have a hostname set for your machine, and this hostname
2316 does not appear in /etc/hosts, you will be able to telnet to port
2317 25 and even send a mail with rcpt to: user@host-not-in-/etc/hosts,
2318 but fetchmail can't seem to get in touch with sendmail, no matter
2319 what you set smtpaddress to.</p>
2321 <p>We had another report from a Linux user of fetchmail 2.1 who
2322 solved his SMTP connection problem by removing the reference to
2323 -lresolv from his link line and relinking. Apparently in some older
2324 Linux distributions the libc bind library version works better.</p>
2326 <p>As of 2.2, the configure script has been hacked so the bind
2327 library is linked only if it is actually needed. So under Linux it
2328 won't be, and this particular cause should go away.</p>
2331 <h2><a id="R2" name="R2">R2. When I try to configure an MDA,
2332 fetchmail doesn't work.</a></h2>
2334 <p>(I hear this one from people who have run into the blank-line
2335 problem in <a href="#X1">X1</a>.)</p>
2337 <p>Try sending yourself test mail and retrieving it using the
2338 command-line options '<code>-k -m cat</code>'. This will dump
2339 exactly what fetchmail retrieves to standard output (plus the
2340 Received line fetchmail itself adds to the headers).</p>
2342 <p>If the dump doesn't match what shows up in your mailbox when you
2343 configure an MDA, your MDA is mangling the message. If it doesn't
2344 match what you sent, then fetchmail or something on the server is
2348 <h2><a id="R3" name="R3">R3. Fetchmail dumps core when given an
2349 invalid rc file.</a></h2>
2351 <p>This is usually reported from AIX or Ultrix, but has even been
2352 known to happen on Linuxes without a recent version of
2353 <code>flex</code> installed. The problem appears to be a result of
2354 building with an archaic version of lex.</p>
2356 <p>Workaround: fix the syntax of your .fetchmailrc file.</p>
2358 <p>Fix: build and install the latest version of <a
2359 href="ftp://prep.ai.mit.edu/~ftp/pub/gnu">flex</a> from the Free
2360 Software Foundation. An FSF <a
2361 href="http://www.gnu.ai.mit.edu/order/ftp.html">mirror site</a>
2362 will help you get it faster.</p>
2365 <h2><a id="R4" name="R4">R4. Fetchmail dumps core in -V mode, but
2366 operates normally otherwise.</a></h2>
2368 <p>We've had this reported to us under Linux using libc-5.4.17 and
2369 gcc-2.7.2. It does not occur with libc-5.3.12 or earlier
2372 <p>Workaround: link with GNU malloc rather than the stock C library
2375 <p>We're told there is some problem with the malloc() code in that
2376 version which makes it fragile in the presence of multiple free()
2377 calls on the same pointer (the malloc arena gets corrupted).
2378 Unfortunately it appears from doing gdb traces that whatever free()
2379 calls producing the problem are being made by the C library itself,
2380 not the fetchmail code (they're all from within fclose, and not an
2381 fclose called directly by fetchmail, either).</p>
2384 <h2><a id="R5" name="R5">R5. Running fetchmail in daemon mode
2385 doesn't work.</a><br/>
2388 <p>We have one report from a SunOS 4.1.4 user that trying to run
2389 fetchmail in detached daemon mode doesn't work, but that using the
2390 same options with -N (nodetach) is OK. We have another report of
2391 similar behavior from one Linux user, but many other Linux users
2392 reportt no problem.</p>
2394 <p>If this happens, you have a specific portability problem with
2395 the code in daemon.c that detaches and backgrounds the daemon
2396 fetchmail. The isolated Linux case has been chased down to a
2397 failure in dup(2) that may reflect a glibc bug.</p>
2399 <p>As a workaround, you can start fetchmail with -N and an
2400 ampersand to background it. A Sun user recommends this:</p>
2403 (fetchmail --nodetach <other params> &)
2406 <p>The extra pair of parens is significant --- it makes sure that
2407 the process detaches from the initial shell (one more shell is
2408 started and dies immediately, detaching fetchmail and making it
2409 child of PID 1). This is important when you start fetchmail
2410 interactively and than quit interactive shell. The line above makes
2411 sure fetchmail lives after that!</p>
2414 <h2><a id="R6" name="R6">R6. Fetchmail randomly dies with socket
2417 <p>Check the MTU value in your PPP interface reported by
2418 <code>/sbin/ifconfig</code>. If it's over 600, change it in your
2419 PPP options file. (<code>/etc/ppp/options</code> on my box). Here
2420 are option values that work:</p>
2427 <p>Another circumstance that can trigger this is if you are polling
2428 a virtual-mail-server name that is round-robin connected to
2429 different actual servers, so you get different IP addresses on
2430 different poll cycles. To work around this, change the poll name
2431 either to the real name of one of the servers in the ring or to a
2432 corresponding IP address.</p>
2435 <h2><a id="R7" name="R7">R7. Fetchmail running as root stopped
2436 working after an OS upgrade</a></h2>
2438 <p>In RH 6.0, the HOME value in the boot-time root environment
2439 changed from /root to / as the result of a change in init. Move
2440 your .fetchmailrc or use a -f option to explicitly point at the
2441 file. (Oddly, a similar problem has been reported from Debian
2445 <h2><a id="R8" name="R8">R8. Fetchmail is timing out after fetching
2446 certain messages but before deleting them</a></h2>
2448 <p>There's a TCP/IP stalling problem under Redhat 6.0 (and possibly
2449 other recent Linuxes) that can cause this symptom. Brian Boutel
2453 <p>TCP timestamps are turned on on my Linux boxes (I assume it's
2454 now the default). This uses 12 extra bytes per segment. When the
2455 tcp connection starts, the other end agrees a MSS of 1460, and then
2456 fragments 1460 byte chunks into 1448 and 12, because is is not
2457 allowing for the timestamp.</p>
2459 <p>Then, for reasons I can't explain, it waits a long time
2460 (typically 2 minutes) after the ack is sent before sending the next
2461 (fragmented) packet. Turning off tcp timestamps avoids the
2462 fragmentation and restores normal behaviour. To do this,
2465 <p>echo 0 > /proc/sys/net/ipv4/tcp_timestamps</p>
2467 <p>I'm still unclear about the details of why this is happening. At
2468 least [now] I am now getting good performance and no queue
2473 <h2><a id="R9" name="R9">R9. Fetchmail is timing out during message
2476 <p>This is probably a general networking issue. Sending a "RETR"
2477 command will cause the server to start sending large amounts of
2478 data, which means large packets. If your networking layer has a
2479 packet-fragmentation problem, that's where you'll see it.</p>
2482 <h2><a id="R10" name="R10">R10. Fetchmail is dying with
2485 <p>This probably means you have an <code>mda</code> option. Your
2486 MDA is croaking while being passed a message. Best fix is to remove
2487 the <code>mda</code> option and pass mail to your port 25 SMTP
2490 <p>If for some reason you are invoking sendmail via the
2491 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
2492 don't forget to include the -i switch. Otherwise you will
2493 occasionally get mysterious delivery failures with a SIGPIPE as the
2494 sendmail instance dies. The problem is messages with a single dot
2495 at start of a text line.</p>
2498 <h2><a id="R11" name="R11">R11. My server is hanging or emitting
2499 errors on CAPA.</a></h2>
2501 <p>Your POP3 server is broken. You can work around this with the
2502 declaration <tt>auth password</tt> in your .fetchmailrc.</p>
2505 <h2><a id="H1" name="H1">H1. Fetchmail hangs when used with
2508 <p>Your problem may be with pppd's 'demand' option. We have a
2509 report that fetchmail doesn't play well with it, but works with
2510 pppd if 'demand' is turned off. We have no idea why this is.</p>
2513 <h2><a id="H2" name="H2">H2. Fetchmail hangs during the MAIL FROM
2516 <p>The symptom: 'fetchmail -v' retrieves mail fine, but appears to
2517 hang after sending the MAIL FROM command</p>
2520 SMTP> MAIL FROM: <someone@somewhere>
2523 <p>The hang is actually occuring when sendmail looks up a sender's
2524 address in DNS. The problem isn't in fetchmail but in the
2525 configuration of sendmail. You must enable the 'nodns' and
2526 'nocanonify' features of sendmail.</p>
2528 <p>Here was my fix for RedHat 7.2:</p>
2531 <li># cd /etc/mail</li>
2533 <li># cp sendmail.mc sendmail-mine.mc</li>
2535 <li>Edit sendmail-mine.mc and add lines:
2543 <li>Build a new sendmail.cf
2546 # m4 sendmail-mine.cf > /etc/sendmail.cf
2550 <li>Restart sendmail.</li>
2553 <p>For more details consult the file
2554 /usr/share/sendmail-cf/README.</p>
2557 <h2><a id="H3" name="H3">H3. Fetchmail hangs while fetching
2560 <p>The symption: 'fetchmail -v' retrieves the first few messages,
2561 but hangs returning:</p>
2564 fetchmail: SMTP< 550 5.0.0 Access denied
2565 fetchmail: SMTP> RSET
2566 fetchmail: SMTP< 250 2.0.0 Reset state
2567 .......fetchmail: flushed
2568 fetchmail: POP3> DELE 1
2569 fetchmail: POP3< +OK marked deleted
2572 <p>Check and see if you're allowing sendmail connections through
2575 <p>Adding 'sendmail : 127.0.0.1' to /etc/hosts.allow could solve
2579 <h2><a id="D1" name="D1">D1. I think I've set up fetchmail
2580 correctly, but I'm not getting any mail.</a></h2>
2582 <p>Maybe you have a .forward or alias set up that you've forgotten
2583 about. You should probably remove it.</p>
2585 <p>Or maybe you're trying to run fetchmail in multidrop mode as
2586 root without a .fetchmailrc file. This doesn't do what you think it
2587 should; see question <a href="#C1">C1</a>.</p>
2589 <p>Or you may not be connecting to the SMTP listener. Run fetchmail
2590 -v and see <a href="#R1">R1</a>.</p>
2592 <p>Or you may have your local user set incorrectly. In the
2596 user 'remoteuser' there with password '*' is 'localuser' here
2599 <p>make sure that 'localuser' does exist and can receive mail.</p>
2602 <h2><a id="D2" name="D2">D2. All my mail seems to disappear after a
2603 dropped connection.</a></h2>
2605 <p>One POP3 daemon used in the Berkeley Unix world that reports
2606 itself as POP3 version 1.004 actually throws the queue away. 1.005
2607 fixed that. If you're running this one, upgrade immediately. (It
2608 also truncates long lines at column 1024)</p>
2610 <p>Many POP servers, if an interruption occurs, will restore the
2611 whole mail queue after about 10 minutes. Others will restore it
2612 right away. If you have an interruption and don't see it right
2613 away, cross your fingers and wait ten minutes before retrying.</p>
2615 <p>Some servers (such as Microsoft's NTMail) are mis-designed to
2616 restore the entire queue, including messages you have deleted. If
2617 you have one of these and it flakes out on you a lot, try setting a
2618 small <code>--fetchlimit</code> value. This will result in more IP
2619 connects to the server, but will mean it actually executes changes
2620 to the queue more often.</p>
2622 <p>Qualcomm's qpopper, used at many BSD Unix sites, is better
2623 behaved. If its connection is dropped, it will first execute all
2624 DELE commands as though you had issued a QUIT (this is a technical
2625 violation of the POP3 RFCs, but a good idea in a world of flaky
2626 phone lines). Then it will re-queue any message that was being
2627 downloaded at hangup time. Still, qpopper may require a noticeable
2628 amount of time to do deletions and clean up its queue. (Fetchmail
2629 waits a bit before retrying in order to avoid a 'lock busy'
2633 <h2><a id="D3" name="D3">D3. Mail that was being fetched when I
2634 interrupted my fetchmail seems to have been vanished.</a></h2>
2636 <p>Fetchmail only sends a delete mail request to the server when
2637 either (a) it gets a positive delivery acknowledgment from the SMTP
2638 listener, or (b) it gets one of the spam-filter errors (see the
2639 description of the <code>antispam></code> option) from the
2640 listener. No interrupt can cause it to lose mail.</p>
2642 <p>However, IMAP2bis has a design problem in that its normal fetch
2643 command marks a message 'seen' as soon as the fetch command to get
2644 it is sent down. If for some reason the message isn't actually
2645 delivered (you take a line hit during the download, or your port 25
2646 listener can't find enough free disk space, or you interrupt the
2647 delivery in mid-message) that 'seen' message can lurk invisibly in
2648 your server mailbox forever.</p>
2650 <p>Workaround: add the '<code>fetchall</code>' keyword to your
2653 <p>Solution: switch to an <a href="http://www.imap.org">IMAP4</a>
2657 <h2><a id="M1" name="M1">M1. I've declared local names, but all my
2658 multidrop mail is going to root anyway.</a></h2>
2660 <p>Somehow your fetchmail is never recognizing the hostname part of
2661 recipient names it parses out of To/Cc/envelope-header lines as
2662 matching the name of the mailserver machine. To check this, run
2663 fetchmail in foreground with -v -v on. You will probably see a lot
2664 of messages with the format "line rejected, %s is not an alias of
2665 the mailserver" or "no address matches; forwarding to %s."</p>
2667 <p>These errors usually indicate some kind of DNS configuration
2668 problem either on the server or your client machine.</p>
2670 <p>The easiest workaround is to add a '<code>via</code>' option (if
2671 necessary) and add enough aka declarations to cover all of your
2672 mailserver's aliases, then say '<code>no dns</code>'. This will
2673 take DNS out of the picture (though it means mail may be
2674 uncollected if it's sent to an alias of the mailserver that you
2675 don't have listed).</p>
2677 <p>It would be better to fix your DNS, however. DNS problems can
2678 hurt you in lots of ways, for example by making your machines
2679 intermittently or permanently unreachable to the rest of the
2682 <p>Occasionally these errors indicate the sort of header-parsing
2683 problem described in <a href="#M7">M7</a>.</p>
2686 <h2><a id="M2" name="M2">M2. I can't seem to get fetchmail to route
2687 to a local domain properly.</a></h2>
2689 <p>A lot of people want to use fetchmail as a poor man's
2690 internetwork mail gateway, picking up mail accumulated for a whole
2691 domain in a single server mailbox and then routing based on what's
2692 in the To/Cc/Bcc lines.</p>
2694 <p>In general, this is not really a good idea. It would be smarter
2695 to just let the mail sit in the mailserver's queue and use
2696 fetchmail's ETRN or ODMR modes to trigger SMTP sends periodically
2697 (of course, this means you have to poll more frequently than the
2698 mailserver's expiration period). If you can't arrange this, try
2699 setting up a UUCP feed.</p>
2701 <p>If neither of these alternatives is available, multidrop mode
2702 may do (though you <em>are</em> going to get hurt by some mailing
2703 list software; see the caveats under THE USE AND ABUSE OF MULTIDROP
2704 MAILBOXES on the man page). If you want to try it, the way to do it
2705 is with the '<code>localdomains</code>' option.</p>
2707 <p>In general, if you use localdomains you need to make sure of two
2710 <p><strong>1. You've actually set up your .fetchmailrc entry to
2711 invoke multidrop mode.</strong></p>
2713 <p>Many people set a '<code>localdomains</code>' list and then
2714 forget that fetchmail wants to see more than one name (or the
2715 wildcard '*') in a '<code>here</code>' list before it will do
2716 multidrop routing.</p>
2718 <p><strong>2. You may have to set 'no envelope'.</strong></p>
2720 <p>Normally, multidrop mode tries to deduce an envelope address
2721 from a message before parsing the To/Cc/Bcc lines (this enables it
2722 to avoid losing to mailing list software that doesn't put a
2723 recipient address in the To lines).</p>
2725 <p>Some ways of accumulating a whole domain's messages in a single
2726 server mailbox mean it all ends up with a single envelope address
2727 that is useless for rerouting purposes. You may have to set
2728 '<code>no envelope</code>' to prevent fetchmail from being
2729 bamboozled by this.</p>
2731 <p>Check also answer <a href="#T1">T1</a> on a reliable way to do
2732 multidrop delivery if your ISP (or your mail redirection provider)
2736 <h2><a id="M3" name="M3">M3. I tried to run a mailing list using
2737 multidrop, and I have a mail loop!</a></h2>
2739 <p>This isn't fetchmail's fault. Check your mailing list. If the
2740 list expansion includes yourself or anybody else at your mailserver
2741 (that is, not on the client side) you've created a mail loop. Just
2742 chop the host part off any local addresses in the list.</p>
2744 <p>If you use sendmail, you can check the list expansion with
2745 <code>sendmail -bv</code>.</p>
2748 <h2><a id="M4" name="M4">M4. My multidrop fetchmail seems to be
2749 having DNS problems.</a></h2>
2751 <p>We have one report from a Linux user (not the same one as in <a
2752 href="#R1">R1</a>!) who solved this problem by removing the
2753 reference to -lresolv from his link line and relinking. Apparently
2754 in some older Linux distributions the libc5 bind library version
2757 <p>As of 2.2, the configure script has been hacked so the bind
2758 library is linked only if it is actually needed. So under Linux it
2759 won't be, and this problem should go away.</p>
2762 <h2><a id="M5" name="M5">M5. I'm seeing long DNS delays before each
2763 message is processed.</a></h2>
2765 <p>Use the '<code>aka</code>' option to pre-declare as many of your
2766 mailserver's DNS names as you can. When an address's host part
2767 matches an aka name, no DNS lookup needs to be done to check
2770 <p>If you're sure you've pre-declared all of your mailserver's DNS
2771 names, you can use the '<code>no dns</code>' option to prevent
2772 other hostname parts from being looked up at all.</p>
2774 <p>Sometimes delays are unavoidable. Some SMTP listeners try to
2775 call DNS on the From-address hostname as a way of checking that the
2776 address is valid.</p>
2779 <h2><a id="M6" name="M6">M6. How do I get multidrop mode to work
2780 with majordomo?</a></h2>
2782 <p>In order for sendmail to execute the command strings in the
2783 majordomo alias file, it is necessary for sendmail to think that
2784 the mail it receives via SMTP really is destined for a local user
2785 name. A normal virtual-domain setup results in delivery to the
2786 default mailbox, rather than expansion through majordomo.</p>
2788 <p>Michael <michael@bizsystems.com> gave us a recipe for
2789 dealing with this case that pairs a run control file like this:</p>
2792 poll your.pop3.server proto pop3:
2794 localdomains virtual.localdomain1.com virtual.localdomain2.com ...
2795 user yourISPusername is root * here,
2796 password yourISPpassword fetchall
2799 <p>with a hack on your local sendmail.cf like this:</p>
2802 #############################################
2803 # virtual info, local hack for ruleset 98 #
2804 #############################################
2806 # domains to treat as direct mapped local domain
2808 CVvirtual.localdomain1.com virtual.localdomain2.com ...
2809 ---------------------------
2811 -------------------------
2812 # handle virtual users
2814 R$+ <@ $=V . > $: $1 < @ $j . >
2815 R< @ > $+ < @ $=V . > $: $1 < @ $j . >
2816 R< @ > $+ $: $1
2817 R< error : $- $+ > $* $#error $@ $1 $: $2
2818 R< $+ > $+ < @ $+ > $: $>97 $1
2821 <p>This ruleset just strips virtual domain names off the addresses
2822 of incoming mail. Your sendmail must be 8.8 or newer for this to
2823 work. Michael says:</p>
2825 <blockquote>I use this scheme with 2 virtual domains and the
2826 default ISP user+domain and service about 30 mail accounts +
2827 majordomo on my inside pop3 server with fetchmail and sendmail
2831 <h2><a id="M7" name="M7">M7. Multidrop mode isn't parsing envelope
2832 addresses from my Received headers as it should.</a></h2>
2834 <p>It may happen that you're getting what appear to be well-formed
2835 sendmail Received headers, but fetchmail can't seem to extract an
2836 envelope address from them. There can be a couple of reasons for
2839 <h3>Spurious Received lines need to be skipped:</h3>
2841 <p>First, fetchmail might be looking at the wrong Received header.
2842 Normally it looks only on the first one it sees, on the theory that
2843 that one was last added and is going to be the one containing your
2844 mailserver's theory of who the message was addressed to.</p>
2846 <p>Some (unusual) mailserver configurations will generate extra
2847 Received lines which you need to skip. To arrange this, use the
2848 optional skip prefix argument of the 'envelope' option; you may
2849 need to say something like '<code>envelope 1 Received</code>' or
2850 '<code>envelope 2 Received</code>'.</p>
2852 <h3>The 'by' clause doesn't contain a mailserver alias:</h3>
2854 <p>When fetchmail parses a Received line that looks like</p>
2857 Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
2858 by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
2859 for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
2862 <p>it checks to see if 'iserv.ttns.net' is a DNS alias of your
2863 mailserver before accepting 'ksturgeon@fbceg.org' as an envelope
2864 address. This check might fail if your DNS were misconfigured, or
2865 if you were using 'no dns' and had failed to declare iserv.ttns.net
2866 as an alias of your server.</p>
2869 <h2><a id="M8" name="M8">M8. Users are getting multiple copies of
2872 <p>It's a consequence of multidrop. What's happening is that you
2873 have N users subscribed to the same list. The list software sends N
2874 copies, not knowing they will end up in the same multidrop box.
2875 Since they are both locally addressed to all N users, fetchmail
2876 delivers N copies to each user.</p>
2878 <p>Fetchmail tries to eliminate adjacent duplicate messages in a
2879 multidrop mailbox. However, this logic depends on the message-ID
2880 being identical in both copies. It also depends on the two copies
2881 being adjacent in the server mailbox. The former is usually the
2882 case, but the latter condition sometimes fails in a
2883 timing-dependent way if the server was processing multiple incoming
2886 <p>I could eliminate this problem by keeping a list of all
2887 message-IDs received during a poll so far and dropping any message
2888 that matches a seen mail ID. The trouble is that this is an O(N**2)
2889 operation that might significantly slow down the retrieval of large
2893 <h2><a id="X1" name="X1">X1. Spurious blank lines are appearing in
2894 the headers of fetched mail.</a></h2>
2896 <p>What's probably happening is that the POP/IMAP daemon on your
2897 mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
2898 something in your delivery path (most likely an old version of the
2899 <em>deliver</em> program, which sendmail often calls to do local
2900 delivery) is failing to recognize it as a header.</p>
2902 <p>This is not fetchmail's problem. The first thing to try is
2903 installing a current version of <em>deliver</em>. If this doesn't
2904 work, try to figure out which other program in your mail path is
2905 inserting the blank line and replace that. If you can't do either
2906 of these things, pick a different MDA (such as procmail) and
2907 declare it with the '<code>mda</code>' option.</p>
2910 <h2><a id="X2" name="X2">X2. My mail client can't see a Subject
2913 <p>First, see <a href="#X1">X1</a>. This is quite probably the same
2914 problem (X-POP3-Rcpt header or something similar being inserted by
2915 the server and choked on by an old version of
2916 <em>deliver</em>).</p>
2918 <p>The O'Reilly sendmail book does warn that IDA sendmail doesn't
2919 process X- headers correctly. If this is your problem, all I can
2920 suggest is replacing IDA sendmail, because it's broken and not
2921 RFC822 conformant.</p>
2924 <h2><a id="X3" name="X3">X3. Messages containing "From" at start of
2925 line are being split.</a></h2>
2927 <p>If you know the messages aren't split in your server mailbox,
2928 then this is a problem with your POP/IMAP server, your client-side
2929 SMTP listener or your local delivery agent. Fetchmail cannot split
2932 <p>Some POP server daemons ignore Content-Length headers and split
2933 messages on From lines. We have one report that the 2.1 version of
2934 the BSD popper program (as distributed on Solaris 2.5 and
2935 elsewhere) is broken this way.</p>
2937 <p>You can test this. Declare an mda of 'cat' and send yourself one
2938 piece of mail containing "From" at start of a line. If you see a
2939 split message, your POP/IMAP server is at fault. Upgrade to a more
2942 <p>Sendmail and other SMTP listeners don't split RFC822 messages
2943 either. What's probably happening is either sendmail's local
2944 delivery agent or your mail reader are not quite RFC822-conformant
2945 and are breaking messages on what it thinks are Unix-style From
2946 headers. You can figure out which by looking at your client-side
2947 mailbox with vi or more. If the message is already split in your
2948 mailbox, your local delivery agent is the problem. If it's not,
2949 your mailreader is the problem.</p>
2951 <p>If you can't replace the offending program, take a look at your
2952 sendmail.cf file. There will likely be a line something like</p>
2955 Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
2958 <p>describing your local delivery agent. Try inserting the 'E'
2959 option in the flags part (the F= string). This will make sendmail
2960 turn each dangerous start-of-line From into a >From, preventing
2961 programs further downstream from acting up.</p>
2964 <h2><a id="X4" name="X4">X4.</a><a id="generic_mangling"
2965 name="generic_mangling">My mail is being mangled in a new and
2966 different way</a></h2>
2968 <p>The first thing you need to do is pin down what program is doing
2969 the mangling. We don't like getting bug reports about fetchmail
2970 that are actually due to some other program's malfeasance, so
2971 please go through this diagnostic sequence before sending us a
2974 <p>There are five possible culprits to consider, listed here in the
2975 order they pass your mail:</p>
2978 <li>Programs upstream of your server mailbox.</li>
2980 <li>The POP or IMAP server on your mailserver host.</li>
2982 <li>The fetchmail program itself.</li>
2984 <li>Your local sendmail.</li>
2986 <li>Your LDA (local delivery agent), as called by sendmail or
2987 specified by <code>mda</code>.</li>
2990 <p>Often it happens that fetchmail itself is OK, but using it
2991 exposes pre-existing bugs in your downstream software, or your
2992 downstream software has a bad interaction with POP/IMAP. You need
2993 to pin down exactly where the message is being garbled in order to
2994 deduce what is actually going on.</p>
2996 <p>The first thing to do is send yourself a test message, and
2997 retrieve it with a .fetchmailrc entry containing the following (or
2998 by running with the equivalent command-line options):</p>
3001 mda "cat >MBOX" keep fetchall
3004 <p>This will capture what fetchmail gets from the server, except
3005 for (a) the extra Received header line fetchmail prepends, (b)
3006 header address changes due to <code>rewrite</code>, and (c) any
3007 end-of-line changes due to the <code>forcecr</code> and
3008 <code>stripcr</code> options. MBOX will in fact contain what
3009 programs downstream of fetchmail see.</p>
3011 <p>The most common causes of mangling are bugs and
3012 misconfigurations in those downstream programs. If MBOX looks
3013 unmangled, you will know that is what is going on and that it is
3014 not fetchmail's problem. Take a look at the other FAQ items in this
3015 section for possible clues about how to fix your problem.</p>
3017 <p>If MBOX looks mangled, the next thing to do is compare it with
3018 your actual server mailbox (if possible). That's why you specified
3019 <code>keep</code>, so the server copy would not be deleted. If your
3020 server mailbox looks mangled, programs upstream of your server
3021 mailbox are at fault. Unfortunately there is probably little you
3022 can do about this aside from complaining to your site postmaster,
3023 and nothing at all fetchmail can do about it!</p>
3025 <p>More likely you'll find that the server copy looks OK. In that
3026 case either the POP/IMAP server or fetchmail is doing the mangling.
3027 To determine which, you'll need to telnet to the server port and
3028 simulate a fetchmail session yourself. This is not actually hard
3029 (both POP3 and IMAP are simple, text-only, line-oriented protocols)
3030 but requires some attention to detail. You should be able to use a
3031 fetchmail -v log as a model for a session, but remember that the
3032 "*" in your LOGIN or PASS command dump has to be replaced with your
3033 actual password.</p>
3035 <p>The objective of manually simulating fetchmail is so you can see
3036 exactly what fetchmail sees. If you see a mangled message, then
3037 your server is at fault, and you probably need to complain to your
3038 mailserver administrators. However, we like to know what the broken
3039 servers are so we can warn people away from them. So please send us
3040 a transcript of the session including the mangling <em>and the
3041 server's initial greeting line</em>. Please tell us anything else
3042 you think might be useful about the server, like the server host's
3043 operating system.</p>
3045 <p>If your manual fetchmail simulation shows an unmangled message,
3046 congratulations. You've found an actual fetchmail bug, which is a
3047 pretty rare thing these days. Complain to us and we'll fix it.
3048 Please include the session transcript of your manual fetchmail
3049 simulation along with the other things described in the FAQ entry
3050 on <a href="#G3">reporting bugs</a>.</p>
3053 <h2><a id="X5" name="X5">X5. Using POP3, retrievals seems to be
3054 fetching too much!</a></h2>
3056 <p>This may happen in versions of fetchmail after 4.4.1 and before
3057 4.4.8. Versions after 4.4.1 use POP3's TOP command rather than
3058 RETR, in order to avoid marking the message seen (leaving it unseen
3059 is helpful for later recovery if you lose your connection in the
3060 middle of a retrieval).</p>
3062 <p>Versions of fetchmail from 4.4.2 through 4.4.7 had a bad
3063 interaction with Eudora qpopper versions 2.3 and later. The TOP
3064 bounds check was fooled by an overflow condition in the TOP
3065 argument. Decrementing the TOP argument in 4.4.7 fixed this.</p>
3067 <p>Fix: Upgrade to a later version of fetchmail.</p>
3069 <p>Workaround: set the <code>fetchall</code> option. Under POP3
3070 this has the side effect of forcing RETR use.</p>
3073 <h2><a id="X6" name="X6">X6. My mail attachments are being dropped
3074 or mangled.</a></h2>
3076 <p>Fetchmail doesn't discard attachments; fetchmail doesn't have any idea
3077 that attachments are there. Fetchmail treats the body of each message as
3078 an uninterpreted byte stream and passes it through without alteration.
3079 If you are not receiving attachments through fetchmail, it is because
3080 your mailserver is not sending them to you.</p>
3082 <p>The fix for this is to replace your mailserver with one that works.
3083 If its operating system makes this difficult, you should replace its
3084 operating system with one that works. Windows- and NT-based POP servers
3085 seem especially prone to mangle attachments. If you are running one
3086 of these, replacing your server with a Unix machine is probably the
3087 only effective solution.</p>
3089 <p>We've had sporadic reports of problems with Microsoft Exchange and
3090 Outlook servers. These sometimes randomly fail to ship
3091 attachments to your client. This is a known bug, acknowledged by
3094 <p>They may also mangle the attachments they do pass through. If you
3095 see unreadable attachments with a ContentType of "application/x-tnef",
3096 you're having this problem. The <a
3097 href="http://world.std.com/~damned/software.html">TNEF</a> utility may
3100 <p>The Mail Max POP3 server and the InterChange and Imail IMAP
3101 servers are known to simply drop MIME attachments when uploading
3104 <p>We've also had a report that Lotus Notes sometimes trashes the
3105 MIME type of messages. In particular, it seems to modify MIME
3106 headers of type application/pdf, mangling the type to
3107 application/octet-stream. It may corrupt other MIME types as
3110 <p>The IMAP service of Lotus Domino has a known bug in the way it
3111 generates MIME Content-type headers (observed on Lotus Domino
3112 5.0.2b). It's a subtle one that doesn't show up when Netscape
3113 Messenger and other clients use a FETCH BODY[] to grab the whole
3114 message. When fetchmail uses FETCH RFC822.HEADER and FETCH
3115 RFC822.TEXT to get first the header and then the body, Domino
3116 generates different Boundary tags for each part, .e.g. one tag is
3117 declared in the Content-type header and another is used to separate
3118 the MIME parts in the body. This doesn't work. (I have heard a
3119 rumor that this bug is scheduled to be fixed in Domino release 6;
3120 you can find a workaround at contrib/domino.)</p>
3122 <p>Rob Funk explains: Unfortunately there also remain many mail
3123 user agents that don't write correct MIME messages. One big
3124 offender is Sun MailTool attachments, which are formatted enough
3125 like MIME that some programs could get confused; these are
3126 generated by the mailtool and dtmail programs (the mail programs in
3127 Sun's OpenWindows and CDE environments).</p>
3129 <p>One solution to problems related to misformatted MIME
3130 attachments is the <a
3131 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/">emil</a>
3133 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/TUTORIAL.html">tutorial</a>
3134 file at that site for details on emil. It is useful for converting
3135 character sets, attachment encodings, and attachment formats. At
3136 this writing, emil does not appear to have been maintained since a
3137 patch to version 2.1.0beta9 in late 1997, but it is still
3140 <p>One good way of using emil is from within procmail. You can have
3141 procmail look for signs of problematic message formatting, and pipe
3142 those messages through emil to be fixed. emil will not always be
3143 able to fix the problem, in which case the message is
3146 <p>A possible rule to be inserted into a .procmailrc file for using
3151 * 1^1 ^Content-Type: \/X-sun[^;]*
3152 * 1^1 ^Content-Type: \/application/mac-binhex[^;]*
3153 * 1^1 ^Content-Transfer-Encoding: \/x-binhex[^;]*
3154 * 1^1 ^Content-Transfer-Encoding: \/x-uuencode[^;]*
3156 LOG="Converting $MATCH
3159 | emil -A B -T Q -B BA -C iso-8859-1 -H Q -F MIME \
3160 | gawk '{gsub(/\r\n?/,"\n");print $0}'
3164 <p>The "1^1" in the conditions is a way of specifying to procmail
3165 that if any one of the four listed expressions is found in the
3166 message, the total condition is considered true, and the message
3167 gets passed into emil. These four subconditions check whether the
3168 message has a Sun attachment, a binhex attachment, or a uuencoded
3169 attachment; there are others that could be added to check these
3170 things better and to check other relevant conditions. The "LOG="
3171 line writes a line into the procmail log; the lone double-quote
3172 beginning the following line makes sure the log entry gets an
3173 end-of-line character. The call to gawk (GNU awk) is for fixing
3174 end-of-line conventions, since emil sometimes leaves those in the
3175 format of the originating machine; it could probably be replaced
3176 with a sed subsitution.</p>
3178 <p>The emil call itself tries to ensure that the message uses:</p>
3181 <li>BinHex encoding for any Apple Macintosh-only attachments</li>
3183 <li>Quoted-Printable encoding for text (when necessary)</li>
3185 <li>Base64 Encoding for binary attachments</li>
3187 <li>iso-8859-1 character set for text (unfortunately emil can't yet
3188 convert from windows-1252 to iso-8859-1)</li>
3190 <li>Quoted-Printable encoding for headers</li>
3192 <li>MIME attachment format</li>
3195 <p>Most of these (the primary exceptions being the character set
3196 and the Apple binary format) are as they should be for good
3197 internet interoperability.</p>
3199 <p>Some mail servers (Lotus Domino is a suspect here) mangle
3200 Sun-formatted messages, so the conversion to MIME needs to happen
3201 before such programs see the message. The ideal is to rid the world
3202 of Sun-formatted messages: don't use mailtool for sending
3203 attachments (it doesn't understand MIME anyway, and most of the
3204 world doesn't understand its attachments, so it really shouldn't be
3205 used at all), and make sure dtmail is set to use MIME rather than
3206 mailtool's format.</p>
3209 <h2><a id="X7" name="X7">X7. Some mail attachments are hanging
3212 <p>This isn't fetchmail's problem either; fetchmail doesn't know
3213 anything about mail attachments and doesn't treat them any
3214 differently from plain message data.</p>
3216 <p>The most usual cause of this problem seems to be bugs in your
3217 network transport layer's capability to handle the very large
3218 TCP/IP packets that attachments tend to turn into. You can test
3219 this theory by trying to download the offending message through a
3220 webmail account; using HTTP for the message tends to simulate
3221 large-packet stress rather well, and you will probably find that
3222 the messages that seem to be choking fetchmail will make your HTTP
3223 download speed drop to zero.</p>
3225 <p>This problem can be caused by subtle bugs in the
3226 packet-reassembly layer of your TCP/IP stack; these often don't
3227 manifest at normal packet sizes. It may also be caused by
3228 malfunctioning path-MTU discovery on the mailserver. Or, if there's
3229 a modem in the link, it may be because the attachment contains the
3230 Hayes mode escape "+++".</p>
3233 <h2><a id="X8" name="X8">X8. A spurious ) is being appended to my
3236 <p>Blame it on that rancid pile of dung and offal called Microsoft
3237 Exchange. Due to the problem described in <a href="#S2">S2</a>, the
3238 IMAP support in fetchmail cannot follow the IMAP protocol 100%.
3239 Most of the time it doesn't matter, but if you combine it with an
3240 SMTP server that behaves unusually, you'll get a spurious ) at
3243 <p>One piece of software that can trigger this is the Interchange
3244 mail server, as used by, e.g., mailandnews.com. Here's what
3247 <p>1. Someone sends mail to your account. The last line of the
3248 message contains text. So at the SMTP level, the message ends with,
3249 e.g. "blahblah\r\n.\r\n"</p>
3251 <p>2. The SMTP handler sees the final "\r\n.\r\n" and recognizes
3252 the end of the message. However, instead of doing the normal thing,
3253 which is tossing out the ".\r\n" and leaving the first '\r\n' as
3254 part of the email body, Interchange throws out the whole
3255 "\r\n.\r\n", and leaves the email body without any line terminator
3256 at the end of it. RFC821 does not forbid this, though it probably
3259 <p>3. Fetchmail, or some other IMAP client, asks for the message.
3260 IMAP returns it, but it's enclosed inside parentheses, according to
3261 the protocol. The message size in bytes is also present. Because
3262 the message doesn't end with a line terminator, the IMAP client
3270 <p>where the ')' is from IMAP.</p>
3272 <p>4. Fetchmail only deals with complete lines, and can't trust the
3273 stated message size because Microsoft Exchange fscks it up.</p>
3275 <p>5. As a result, fetchmail takes the final 'blahblah)' and puts
3276 it at the end of the message it forwards on. If you have verbosity
3277 on, you'll get a message about actual != expected.</p>
3279 <p>There is no fix for this. The nuke mentioned in <a
3280 href="#S2">S2</a> looks more tempting all the time.</p>
3283 <h2><a id="O1" name="O1">O1. The --logfile option doesn't work if
3284 the logfile doesn't exist.</a></h2>
3286 <p>This is a feature, not a bug. It's in line with normal practice
3287 for system daemons and allows you to suppress logging by removing
3288 the log, without hacking potentially fragile startup scripts. To
3289 get around it, just touch(1) the logfile before you run fetchmail
3290 (this will have no effect on the contents of the logfile if it
3291 already exists).</p>
3294 <h2><a id="O2" name="O2">O2. Every time I get a POP or IMAP message
3295 the header is dumped to all my terminal sessions.</a></h2>
3297 <p>Fetchmail uses the local sendmail to perform final delivery,
3298 which Netscape and other clients doesn't do; the announcement of
3299 new messages is done by a daemon that sendmail pokes. There should
3300 be a "biff" command to control this. Type</p>
3306 <p>to turn it off. If this doesn't work, try the command</p>
3312 <p>which is essentially what <code>biff -n</code> will do. If this
3313 doesn't work, comment out any reference to "comsat" in your
3314 /etc/inetd.conf file and restart inetd.</p>
3316 <p>In Slackware Linux distributions, the last line in /etc/profile
3329 to solve the problem system-wide.
3332 <h2><a id="O3" name="O3">O3. Does fetchmail reread its rc file
3333 every poll cycle?</a></h2>
3335 <p>No, but versions 5.2.2 and later will notice when you modify
3336 your rc file and restart, reading it.</p>
3339 <h2><a id="O4" name="O4">O4. Why do deleted messages show up again
3340 when I take a line hit while downloading?</a></h2>
3342 <p>Because you're using a POP3 other than Qualcomm qpopper, or an
3343 IMAP with a long expunge interval.</p>
3345 <p>According to the POP3 RFCs, deletes aren't actually performed
3346 until you issue the end-of-session QUIT command. Fetchmail cannot
3347 fix this, because doing it right takes cooperation from the server.
3348 There are two possible remedies:</p>
3350 <p>One is to switch to qpopper (the free POP3 server from Qualcomm,
3351 the Eudora people). The qpopper software violates the POP3 RFCs by
3352 doing an expunge (removing deleted messages) on a line hangup, as
3353 well as on processing a QUIT command.</p>
3355 <p>The other (which we recommend) is to switch to <a
3356 href="http://www.imap.org">IMAP</a>. IMAP has an explicit expunge
3357 command and fetchmail normally uses it to delete messages
3358 immediately after they are downloaded.</p>
3360 <p>If you get very unlucky, you might take a line hit in the window
3361 between the delete and the expunge. If you've set a longer expunge
3362 interval, the window gets wider. This problem should correct itself
3363 the next time you complete a successful query.</p>
3366 <h2><a id="O5" name="O5">O5. Why is fetched mail being logged with
3367 my name, not the real From address?</a></h2>
3369 <p>Because logging is done based on the address indicated by the
3370 sending SMTP's MAIL FROM, and some listeners are picky about that
3373 <p>Some SMTP listeners get upset if you try to hand them a MAIL
3374 FROM address naming a different host than the originating site for
3375 your connection. This is a feature, not a bug -- it's supposed to
3376 help prevent people from forging mail with a bogus origin site.
3377 (RFC 1123 says you shouldn't do this exclusion...)</p>
3379 <p>Since the originating site of a fetchmail delivery connection is
3380 localhost, this effectively means these picky listeners will barf
3381 on any MAIL FROM address fetchmail hands them with an @ in it!</p>
3383 <p>Versions 2.1 and up try the header From address first and fall
3384 back to the calling-user ID. So if your SMTP listener isn't picky,
3385 the log will look right.</p>
3388 <h2><a id="O6" name="O6">O6. I'm seeing long sendmail delays or
3389 hangs near the start of each poll cycle.</a></h2>
3391 <p>Sendmail does a hostname lookup when it first starts up, and
3392 also each time it gets a HELO in listener mode.</p>
3394 <p>Your resolver configuration may be causing one of these lookups
3395 to fail and time out. Check <code>/etc/resolv.conf</code> and
3396 <code>/etc/hosts</code> file. Make sure your hostname and
3397 fully-qualified domain name are both in <code>/etc/hosts</code>,
3398 and that hosts is looked at before DNS is queried. You probably
3399 also want your remote mail server(s) to be in the hosts file.</p>
3401 <p>You can suppress the startup-time lookup if need to by
3402 reconfiguring with <code>FEATURE(nodns)</code>.</p>
3404 <p>Configuring your bind library to cache DNS lookups locally may
3405 help, and is a good idea for speeding up other services as well.
3406 Switching to a faster MTA like qmail or exim might help.</p>
3409 <h2><a id="O7" name="O7">O7. Why doesn't fetchmail deliver mail in
3410 date-sorted order?</a></h2>
3412 <p>Because that's not the order the server hands it to fetchmail
3415 <p>Fetchmail getting mail from a POP server delivers mail in the
3416 order that your server delivers mail. Fetchmail can't do anything
3417 about this; it's a limitation of the underlying POP protocol.</p>
3419 <p>In theory it might be possible for fetchmail in IMAP mode to
3420 sort messages by date, but this would be in violation of two basics
3421 of fetchmail's design philosophy: (a) to be as simple and
3422 transparent a pipe as possible, and (b) to <em>hide</em>, rather
3423 than emphasize, the differences between the remote-fetch protocols
3426 <p>Re-ordering messages is a user-agent function, anyway.</p>
3429 <h2><a id="O8" name="O8">O8. I'm using pppd. Why isn't my monitor
3430 option working?</a></h2>
3432 <p>There is a combination of circumstances that can confuse
3433 fetchmail. If you have set up demand dialing with pppd, and pppd
3434 has an idle timeout, and you have lcp-echo-interval set, then the
3435 lcp-echo-interval time must be longer than the pppd idle timeout.
3436 Otherwise it is going keep increasing the packet counters that
3437 fetchmail relies upon, triggering fetchmail into polling after its
3438 own delay interval and thus preventing the pppd link from ever
3439 reaching its inactivity timeout.</p>
3442 <h2><a id="O9" name="O9">O9. Why does fetchmail keep retrieving the
3443 same messages over and over?</a></h2>
3445 <p>First, check to see that you haven't enabled the
3446 <cite>keep</cite> and <cite>fetchall</cite> option. If you have,
3447 turn <cite>keep</cite> off.</p>
3449 <p>There are various forms of lossage involving the POP3 UIDL
3450 feature that can lead to all your old messages being seen again
3451 after a line drop. I have given up trying to fix these, as the UIDL
3452 code breaks worse every time I touch it. The problem is
3453 fundamental; maintaining and garbage-collecting the right kind of
3454 client-side state is just hard. Whoever put UIDLs in RFC1725 and
3455 removed LAST should be hung up by his thumbs and whipped with
3456 scorpions. The right answers are either (a) live with the
3457 occasional breakage, (b) switch to IMAP4, or (c) fix the code
3458 yourself and send me a patch. Unless you choose (c), I don't want
3459 to hear about it.</p>
3461 <p>This can also happen when some other mail client is logged in to
3462 your mail server, if it uses a simple exclusive-locking scheme (and
3463 many, especially most POP3 servers, do exactly that). Your
3464 fetchmail is able to retrieve the messages, but because the mailbox
3465 is write-locked by the other instance yours can neither mark
3466 messages seen or delete them. The solution is to either (a) wait
3467 for the other client to finish, or (b) terminate it.</p>
3469 <p>James Stevens <James.Stevens at kyzo.com> writes:</p>
3471 <p><em>We had a Linux box dialing the Net and collecting mail from
3472 an NT POP3 server. Fetchmail was correctly collecting and deleting
3473 each e-mail one by one. However,the dial-up connection was very
3474 unreliable and would often just drop out in the middle of a
3477 <p><em>Interestingly, unless the TCP POP3 connection was terminated
3478 normally (I guess with a POP3 "QUIT" command) NT would then roll
3479 back all the deletes !!!</em></p>
3481 <p><em>This meant if the first e-mail was very large it might just
3482 end up continuously collecting it, basically jamming the queue. Or,
3483 if the queue became very full itmight never get a long enough phone
3484 connection to retrieve the entire mailbox, and NT would roll back
3485 any deletes, so it would end up collecting (and delivering) the
3486 first few e-mails again and again. As the POP3 mailbox became
3487 fuller and fuller the chances of getting a connection long enough
3488 to collect theentire mailbox became smaller and smaller.</em></p>
3490 <p><em>Our solution was to make fetchmail only collect a few (say 5
3491 or 10) e-mails at atime, thus trying to ensure that the POP3
3492 connection is terminated correctly.</em></p>
3494 <p>Unfortunately, this is exactly the way POP3 servers are supposed
3495 to behave on a line drop, according to the RFCs. I recommend
3496 switching to IMAP and using a short expunge interval.</p>
3499 <h2><a id="O10" name="O10">O10. Why is the received date on all my
3500 messages the same?</a></h2>
3502 <p>This is a design choice in your MTA, not fetchmail. It's taking
3503 the received date from the last Received header.</p>
3506 <h2><a name="O11">O11. I keep getting messages that say "Repoll
3507 immediately" in my logs.</a></h2>
3509 <p>This is your server barfing on the CAPA probe that fetchmail sends.</p>
3511 <p>If you run fetchmail in daemon mode (say "set daemon 600"), you will
3512 get the message only once per run.</p>
3514 <p>If you set an authentication method explicitly (say, with
3515 <code>auth password</code>), you will never get the message.</p>
3518 <h2><a name="O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a></h2>
3520 <p>This is a feature, not a bug.</p>
3522 <p>Any 4xx response (like 451) indicates a transient (temporary) error.
3523 This means that the mail could be accepted if retried later. Lookup
3524 failures are normally transient errors as a mail should not get
3525 rejected if a dns server is unreachable or down.</p>
3527 <p>A permanent reject response is of the form 5xx (like 550).</p>
3529 <p>You could tell your SMTP server to not lookup any addresses if you are
3530 not keen on checking the sender addresses. This problem typically
3531 occurs if your mail server is not checking the sender addresses, but
3532 your local server is.</p>
3534 <p>Or you could declare <code>antispam 451</code>.</p>
3536 <p>Or, you could check your nameserver configuration and query logs for
3539 <p>All these issues are not related to fetchmail directly.</p>
3542 <h2><a name="O13">O13. I want timestamp information in my fetchmail logs.</a></h2>
3544 <p>Write a <code>preconnect</code> command in your configuration file that
3545 does something like "date >> $HOME/Procmail/fetchmail.log".</p>
3548 <table width="100%" cellpadding="0" summary="Canned page footer">
3550 <td width="30%">Back to <a href="index.html">Fetchmail Home
3552 <td width="30%" align="right">$Date: 2004/01/13 08:46:00 $</td>
3557 <address>Eric S. Raymond <a
3558 href="mailto:esr@thyrsus.com"><esr@thyrsus.com></a></address>
3562 compile-command: "(cd ~/WWW; upload fetchmail/fetchmail-FAQ.html)"