Duplicate Message-ID,UIDL,leave on server,repeated downloads of em

J

JS

We have had 2 instances this week with hosting account customers where a user
is experiencing issues with Outlook 12 on XP Vista retrieving the same few
email messages over and over. Both users have Outlook set to 'leave a copy of
messages on server' (non-negotiable) and are also using a phone (one BB, one
iPhone) to retrieve via POP. In both cases, their phone are only always
retrieving a single copy of each message.

We have narrowed it down to the fact that when there are 2 or more messages
in the raw mailbox file with the same or same-starting (I will elaborate
later) Message-IDs, Outlook keeps sending RETR commands for these specific
messages.

A user may receive 2 messages with identical Message-IDs when they are
receiving mail in the box for multiple addressees and a single message was
addressed to both. i.e. 'bob receives mail for bob@ and info@ in his mailbox.
Someone sends a single message addressed
To: (e-mail address removed); (e-mail address removed)
with the result:
Message-ID: <[email protected]>
Message-ID: <[email protected]>
The server UIDL command returns these as is:
167 <[email protected]>
168 <[email protected]>


In the other case, the messages have different Message-IDs. They are all
from the same sender who has his Outlook 2003 set to request Delivery
Receipts (DSN). Those Message-IDs crafted by Outlook, though unique, only
differ at the end half ... and are quite a bit longer than most (though well
within acceptable standards):
Message-ID:
<!~!UENERkVCMDkAAQACAAAAAAAAAAAAAAAAABgAAAAAAAAAjXPUkQnEVUK5LEBPxKoFLsKAAAAQAAAA2sN8JwcbKkS9v5P1xvD/[email protected]>

Message-ID:
<!~!UENERkVCMDkAAQACAAAAAAAAAAAAAAAAABgAAAAAAAAAjXPUkQnEVUK5LEBPxKoFLsKAAAAQAAAAK4xHVxmiOUqszBVlhsxrjgEAAAAA@domain.tld>

The problem here is that the server response to the UIDL command appears to
truncate the Message-ID:
23 <!~!UENERkVCMDkAAQACAAAAAAAAAAAAAAAAABgAAAAAAAAAjXPUkQnEVUK5LEBPxKoFLs
42 <!~!UENERkVCMDkAAQACAAAAAAAAAAAAAAAAABgAAAAAAAAAjXPUkQnEVUK5LEBPxKoFLs

Suddenly a message which was retrieved days ago, starts being retrieved
again into Outlook along with the newer ones, and both repeatedly download
each time Outlook does a send/retrieve. And for these, due to the DSN, it's
sending out and the sender is receiving multiple receipts too!

Those are Outlook 2003 generated IDs (when DSN is on). I notice that another
user's Outlook 12 generated IDs (when DSN is on) differ earlier on in the
string:
Message-ID:
<!~!UENERkVCMDkAAQACAAAAAAAAAAAAAAAAABgAAAAAAAAAjXPUkQnEVUK5LEBPxKoFLs ||
TRUNCATING POINT || (e-mail address removed)>

Message-ID:
<!&!AAAAAAAAAAAYAAAAAAAAAAnBLb67zy5IuFH1zuoyrt3CgAAAEAAAAGmpaNx+RZtHik+mSY/mK/[email protected]>
Message-ID:
<!&!AAAAAAAAAAAYAAAAAAAAAAnBLb67zy5IuFH1zuoyrt3CgAAAEAAAAD1qXgqaxDZHvdBrShwpnLwBAAAAAA==@domain2.tld>
Message-ID:
<!&!AAAAAAAAAAAYAAAAAAAAAAnBLb67zy5IuFH1zuoyrt3CgAAAEAAAAEqnDTKWbgNNmDCS/[email protected]>
Message-ID:
<!&!AAAAAAAAAAAYAAAAAAAAAAnBLb67zy5IuFH1zuoyrt3CgAAAEAAAADtNpyq7Q8dNvCxiyIlUSTsBAAAAAA==@domain2.tld>
Message-ID:
<!&!AAAAAAAAAAAYAAAAAAAAAAnBLb67zy5IuFH1zuoyrt3CgAAAEAAAAMustBtNZc5OjOWpEQ72Ip4BAAAAAA==@domain2.tld>

For one user, we actually edited the raw mailbox file and changed the
similar Message-IDs by adding sequential numbers at the beginning:
<!~!1UENERkVCMDkAAQA
<!~!2UENERkVCMDkAAQA
<!~!3UENERkVCMDkAAQA ... up to 6
After downloading all 6 once more, the problem stopped.


So where is the problem? Is it with the sending Outlook 2003 generating IDs
which do not differ enough in the first X characters? Should/could the POP
server be mangling them into more Unique IDs for the UIDL response? Is it
with the receiving Outlook confused and unable to properly determine whether
is has already downloaded the messages and re-requests all of the conflicting
ones to be safe (Recall, the phones are able to determine correctly)? Or is
the receiving Outlook actually sending a request for the new message only and
the POP server is confused and resends all of the conflicting ones?

We have located a hotfix for an earlier version of Outlook:
http://support.microsoft.com/kb/872839/en-us
Duplicate e-mail messages are downloaded from POP3 accounts that supports
UIDL or TOP
If you download e-mail messages from a POP3 account that supports UIDL or
TOP, some e-mail messages may not be deleted after downloading. Therefore,
you may download some duplicate e-mail messages.

It is unclear if this is for the sending Outlook (craft more unique IDs?) or
the receiving Outlook (change the way it determines the messages it already
got?) At any case, it's not applicable for the XP Vista Outlook 12 which is
the one sending the repeated RETR commands. Is something wrong with these
versions:?

The ones repeatedly retrieving the messages are
X-Mailer: Microsoft Office Outlook 11
X-Mailer: Microsoft Office Outlook 12.0 (on XP)

The ones generating similar IDs are:
X-Mailer: Microsoft Outlook, Build 10.0.6838 (on XP)
2 unaffiliated persons using X-Mailer: Microsoft Office Outlook, Build
11.0.5510

Outlook 12.0 is generating different enough IDs.
 
R

Roady [MVP]

Are there any tools in between Outlook and the server which tie into the
send/receive process? Namely virus scanners and 3rd party anti-spam tools?
Disable their integration with Outlook and see what happens now.



-----
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Top