Jeremy Kelly is reporting an unusual interaction between Entourage and Exchange 2003. The symptom: transaction log bloat. The problem seems to occur when an Entourage client tries to submit a message that’s too large for the maximum message size limit set on that user’s mailbox store. Instead of reporting the error (and not resubmitting the message), Entourage happily tries to send the message each time it connects. If the message is large enough, and if this goes on long enough, the server will eventually run out of log space. Jeremy recommends a temporary fix of turning off httpdav, removing the offending message from the client, and re-enabling httpdav; no word yet on an ETA for a better fix.
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Microsoft has a hotfix for this problem now– see http://support.microsoft.com/kb/889525.
We recently had a problem where one of our mailbox servers was generating Excessive transaction logs. We knew the cause was probably related to http://support.microsoft.com/?kbid=889525 because we have some Entourage clients in our environment. We were able to confirm this by examining the IIS logs. Entourage essentially communicates with Exchange like a front end server would (through WebDav). We found that the IIS / W3svc logs showed all the Entourage connections. The command below allowed us to parse through the logs and output only the Entourage connections. It allowed us to identify several users that were not configured correctly.
From the folder where the logs in question are in, run the following command:
FOR %A IN (*.log) DO FIND /i “DavMailSubmissionURI” %A > %A_mailsubmit.log
**For Google: Entourage connections Exchange WebDav Logs