I have a client who is having a problem with users using POP3 on their Exchange 2003 server.
The server is a backend server, the users are connecting over PPTP VPN, the server has all OS and Exchange SPs and patches onboard.
From time to time, a message will block them from downloading their mail, and they will not be able to send/receive until the message is removed from their mailbox.
The client believes that it is messages from outside their organisation (ie they came in via SMTP) with attachments, I have not been able to confirm this fact for myself as yet.
The clients are all using Outlook 2000, but I have connected and tried to use Outlook 2003 and the result is the same.
Outlook 2003 is more communicative about what happens. Down the bottom right, where it gives you a report of the send and receive progress it will tell me how many messages there are to be downloaded, which one I am on and the size.
If I leave just the bad message in the inbox, I get "Receiving message 1 of 1 (746KB of 747KB)" The size goes from 1kb->746 very quickly (it is a fast link) and then sits at 1kb under the total size, after about 2 minutes it times out with at 0x8004210a error - something along the lines of
"the operation timed out waiting for a response from the receiving (POP) server" (unfortunately I don't have the exact error to hand)
Once we remove the suspect message, they are able to send and receive as normal until the next problem.
Any suggestions on this one?