Hi, i am the new one;) - and my first post is about a problem i ran into.

I installed a mailserver on a RaspberryPi. It works mostly well, using dovecot 2.1.7. (exim4 4.8 (not in use, smtp direct to Provider), fetchmail 6.3.21, RasPi 3.12.28+, Roundcube (no version known) - the whole system went through an apg-get update/uppgrade this night to look if a known problem already been fixed.

When getting bigger Attachments (not sure if it occurs by smaller too, but bigger attachments are normally "to open" and often fail) Not all of them, but much. Unpredictable when it occurs. These Attachments are shown with less size in the Mailclient (Thunderbird actual version). In Roundcube they are shown to small, too. But it looks as the mail IS "fullsized" on the lokal Mailserver: When i use Roundcube and try to open an x00kB .zip, Roundcube starts to get the whole xyMB (real size) .zip-file, even when disconnected from internet. Thunderbird behaves different, doesnt load the full file, so "ignore" is no option;) And yes, i always dont like that option:)

Beside the lokal mailserver-account(s) there is/are pulled Mails via imap direct from the mailprovider, the "old" solution which shall be replaced by the new mailserver. imap direct from provider shows the mails/Attachments in corrects size an opening works. Only using the local mailserver fails.

In the log-files i found (i quote a part in which - cronjob matching - one of these defect mails was pulled): In Syslog: Mar 26 09:40:01 raspberrypi /USR/SBIN/CRON[26696]: (info) CMD (/usr/bin/fetchmail -s --fetchsizelimit 0 --fetchlimit 0 --limit 0 --timeout 300) Mar 26 09:40:05 raspberrypi dovecot: imap(info): Error: Next message unexpectedly lost from mbox file /home/info/mail/.INBOX at 1066141935 (cached) Mar 26 09:40:05 raspberrypi dovecot: imap(info): Error: read(/home/info/mail/.INBOX) failed: Invalid argument (FETCH for mailbox INBOX UID 1247) Mar 26 09:40:05 raspberrypi dovecot: imap(info): Disconnected: Internal error occurred. Refer to server log for more information. [2015-03-26 09:40:05] in= 2693 out=172626 Mar 26 09:40:07 raspberrypi dovecot: imap(info): Panic: file mbox-sync.c: line 1286 (mbox_sync_handle_eof_updates): assertion failed: (trailer_size <= 2) Mar 26 09:40:07 raspberrypi dovecot: imap(info): Fatal: master: service(imap): child 26341 killed with signal 6 (core dumps disabled) Mar 26 09:40:51 raspberrypi dovecot: imap-login: Login: user=<info>, method=PLAIN, rip=192.168.100.27, lip=192.168.100.199, mpid=26723, TLS, session= Mar 26 09:42:16 raspberrypi dovecot: imap(info): Connection closed in=752 out=21810

And in mail.err: Mar 26 09:40:05 raspberrypi dovecot: imap(info): Error: Next message unexpectedly lost from mbox file /home/info/mail/.INBOX at 1066141935 (cached) Mar 26 09:40:05 raspberrypi dovecot: imap(info): Error: read(/home/info/mail/.INBOX) failed: Invalid argument (FETCH for mailbox INBOX UID 1247) Mar 26 09:40:07 raspberrypi dovecot: imap(info): Panic: file mbox-sync.c: line 1286 (mbox_sync_handle_eof_updates): assertion failed: (trailer_size <= 2) Mar 26 09:40:07 raspberrypi dovecot: imap(info): Fatal: master: service(imap): child 26341 killed with signal 6 (core dumps disabled)

(To tell the whole story: /home/$user/mail is link by NFS to a NAS. The limit 0 and timeout entries are just to test after running into the error and before i discovered that not fetchmail but dovecot looks to cause the problem)

In the archive i only found an issue in 2010 with a CR/LF-problem, but it is a) a long time ago an b) i am not sure that my specific problem comes from the same direction. http://www.dovecot.org/list/dovecot/2010-November/054938.html

Any suggestions how to solve that problem?

Thanks.