We have an Exchange Server that on occassions (and what appears to be completly random) rejects messages with the following:
did not reach the following recipient(s):USER@DOMAIN,co.uk on Fri Mar 27 05:13:25 2009 The e-mail account does not exist at the organization this messagewas sent to. Check the e-mail address, or contact the recipientdirectly to find out the correct address.<SERVER.DOMAIN.LOCAL #5.1.1>
However, the address does exist!!!
If I use tracking, it says the message has left the organisation.
It is a Windows Server 2003 Std, and Exchange 2003. Both are fully updated.
The same user can try again in half and hour and all is OK.