Follow-Up: Unable to update seen flag for some mailboxes

[Patrick Goetz]

Yesterday I posted a question to this list regarding a problem I was
having with the mailboxes for some users on cyrus 2.1.15; namely
previously read messages were being marked as "unread" every time the
mailbox listing was refreshed by the IMAP server.  One thing I didn't make
clear was that this problem was independent of MUA:  using pine
directly on the mailhost was no better than using Thunderbird on a Windows
client; as soon as pine was quit and restarted, the "N" would reappear on
previously viewed messages.

In any case, I tried several things including

 - restarting the cyrus master daemon
 - checking ownership and permissions on all the cyrus database files
 - running ctl_cyrusdb -r

None of this worked, and all the permissions/ownership on the database
files was correct.

The only thing which worked was deleting this file:

  /var/lib/cyrus/user/t/this_user/this_user.seen

Steps:
1. Stop cyrmaster
2. rm /var/lib/cyrus/user/t/this_user/this_user.seen
3. Start cyrmaster

the this_user.seen db file was automatically recreated and read messages
stayed read between restarts of the MUA.

I suppose that a drawback of simply deleting the seen database file is
that all information about which messages have been read is lost, but it's
not at all clear at this point that there was any alternative.