The following config has been stable for years:
Outllook 2000 on Win2K-SP4 clients. NT4-SP6a Exchange 5.5 SP4 server. Exchange DB size 6Gb 100 identical users, one LAN
Suddenly any email with an attachment (any file type, even *.txt) is sitting in the outbox and not sent. Attachment cannot then be opened. Received emails cannot have their attachments opened. Error is "Could not open one or more attachments".
Ran Exchange tools at the weekend and it found a couple of errors. Ran again until clear.
System was OK for 36 hours, but problem has just come back again.
I do not know what to do - stopping the Exchange in working hours is a no-no, but so is no attachments! I cannot switcg virus checker (Macafee) off while system is live.