What you're describing has been a symptom of a corrupted index/uidlist our experience. Now *what's* corrupting it, depends on your setup.
Just to clarify, you're using a single dovecot IMAP/POP3 mail server and not multiple servers, correct?
And equally important, are you using a NFS backend for the Maildirs?
If so, read these:
http://wiki.dovecot.org/NFS http://dovecot.org/list/dovecot/2010-May/049031.html
And look into this: http://wiki2.dovecot.org/Director
If not, check the log files, are you getting corrupted index errors for the users in question? Check their quotas, are they all under?
If they're at quota, then dovecot can't update the index or uidlist for that user. One solution:
http://www.mailinglistarchive.com/html/dovecot@dovecot.org/2010-08/msg01028....
That's what first comes to mind for me.
- Eric Broch ebroch@whitehorsetc.com [2011-10-10 13:04:44 -0600]:
I have dovecot 2.0.11 installed on a CentOS 5.7 email server. Two of the server email clients, one using Outlook and the other Thunderbird, have had all the contents of their inbox disappear only to reappear at a later time. One client's inbox email reappeared upon receiving a test email (to check if it would show up in the inbox) from another user. Has anyone heard of such a thing?
Here's a dump of my dovecot configuration.
-- Tom Pawlowski OIT-CSS System Administrator office: Hill 147 email: tompru@jla.rutgers.edu phone: (732) 445-2634