On Thu, 2011-03-03 at 14:53 +0100, francwalter@gmx.net wrote:
In one account on my server all mails are unread all the time. If i set them as read in my client (IMAP with Mac Mail 4.4 or IMAP with Squirrelmail, it doesn’t matter) they seem to be checked as read for some minutes or less, but very soon they are unread again, so i guess, only my client thinks that they are read, but after the next check, the client reads again that they are unread.
Most likely one of your clients sets them unread for some reason. Have you tried shutting down all your IMAP clients and then using only e.g. Squirrelmail for a while?
Enabling http://wiki.dovecot.org/Plugins/MailLog and looking at the logs might show something useful too.
Now i don’t know where to look or change the “Has been read”-Flag in the maildir-directory. Is it in some file or where is it, the flag?
Like Willie said, it's part of the filename. You could also check if the file's ctime changes unexpectedly (i.e. it changes when filename changes = when flags change).