The situation is this:
Windows 2003 SBS, Exchange 2003, Outlook 2007. Small office that uses one person's calendar ('the doctor') to schedule all events/meetings/etc. The error we are getting is a standard Exchange bounceback error, saying the account in question does not exist. It doesn't. It hasn't existed for more than a year. So when he creates a calendar event and invites people (doesn't matter who), if they click 'send response' to his invitation, it sends the error message to him. If someone else creates a calendar item and invites him, it sends the error message to that person. It only seems to occur when he is the inviter or invitee, but if his account isn't involved, it doesn't occur (despite it being on his calendar).
I've dug around in Exchange and AD and verified that the test account being referenced in the bounceback does not in fact exist anywhere in our system. As a temporary fix, we attempted to recreate said account to see if the messages would then forward to it properly, but no luck. What I did notice is that the failed message in Exchange appears to be routing to an AD object, and not an email address. Unfortunately I'm not familiar enough with exchange to know why it would do that.
A correctly sent message in Message Tracking Center shows:
From: Doctor SoandSo
To: Name1@name1.com, Name2@name2.com, etc etc
The failed one giving the error looks like:
From: Doctor Soandso
To: /O='DomainName'/OU=FIRST ADMINISTRATIVE GROUP/CN=RECIPIENTS/CN='TestAccountName'
(Note I altered that slightly, but you get the idea.)
I, and my co-admin, are completely stumped, since we can't find any reference to the test account in any system anywhere (his PC or on the server in any form) and this message 'randomly' started cropping up about two months ago. It's not actually preventing any real functions, but it's highly annoying and we've as yet been unable to find the source. If anyone has any ideas, we would really appreciate the help.