The behavior that you report is consistant with client timeouts; the
client is not allowing the process to complete, and aborts it. There are
multiple possibilities as for "which process" is getting aborted. In
POP3, the likely candidates are the message download, the mailbox update
with new UID information, the mailbox update with message deletions, etc.
So, the very first thing is to check the user's client configuration and
make sure that any timeouts. Outlook in particular is notorious for short
timeouts; the setting to fix is hidden under "Advanced" settings in the
"Internet E-mail Settings" panel.
Next, check the sizes of the affected mailboxes in question. If the user
has accumulated 1GB of traditional UNIX format mailbox file, that is an
excellent reason for why it needs more time. Traditional UNIX format
mailboxes should not be allowed to exceed more than a few 10s of MB; that
format simply is not suitable for large mailboxes (some other formats are
suitable).
Since both Thunderbird and Outlook support IMAP, another measure would be
for those users to switch to IMAP. IMAP is quite a bit more communicative
about mailbox and message status than POP3.
Finally, I doubt very much that there is some virus or trojan that is
causing this problem. A much more likely explanation is a bloated mailbox
and a client that fails to wait long enough.
However, there is one thing to check; see if the user is receiving spam or
other nuisance mail with fake "X-UID" header lines. This problem only
occurs with traditional UNIX mailbox format, but could indeed cause the
UID regime to get rebuilt. This would be especially the case if it
doesn't happen all the time (e.g., not with repeated sessions on the same
day), but rather a day or so apart.
The best way to cure this is to use another mailbox format which does not
require that message metadata be stored in the message header. Otherwise,
use your spam filtering software to divert messages with headers such as
X-UID to the user's spam bucket.
On Fri, 27 Oct 2006, Brian Thompson wrote:
More info - I just heard from another user here who is running
MS Outlook via pop3, so it doesn't appear to be limited to
Mozilla/Thunderbird.
-Brian
Brian Thompson wrote:
Just recently over the past few days a number of users have been
complaining that their inbox is duplicating itself and they're ending
up with doubles and triples of the same emails in their inbox. It
seems to be related to the mail client downloading their entire inbox
from the server (again) and adding it to the previous stored copy
on their local hard disk.
Nothing has changed regarding our site configuration for the past
few years and this is the first I've heard of the problem, so my
current thinking is that it must be some sort of virus/trojan or a
piece of corrupt email that was received. It also appears to only
be targeting those who are using Mozilla/Thunderbird connected
to the mail server via uw-pop3d.
I'm definitely not complaining or trying to point fingers - just
wondering if anyone has (just recently) run into the same issue
and whether they've figured out what is causing it. The version
of uw-pop3d that we're running is 2004.89. I thought about
upgrading it but would like to track down the cause of the problem
vs. blindly making changes hoping to fix it.
Thanks for any info.
-Brian
_______________________________________________
Imap-uw mailing list
[email protected]
https://mailman1.u.washington.edu/mailman/listinfo/imap-uw
-- Mark --
http://staff.washington.edu/mrc
Science does not emerge from voting, party politics, or public debate.
Si vis pacem, para bellum.
_______________________________________________
Imap-uw mailing list
[email protected]
https://mailman1.u.washington.edu/mailman/listinfo/imap-uw
