Exchange error 5.6.1, "recipient changed address permanently..."
Posted on 2005-05-13
We are trying to resolve an ongoing issue with a mailbox on our Exchange 2003 server (in a Windows 2003 domain). When sending a message to this mailbox via a global distribution list or global security group (user is a member of the list/group), the sender gets the returned message with error # 5.6.1:
"The following recipient(s) could not be reached: Lastname, Firstname on 5/9/2005 8:00 AM
The message was undeliverable because the recipient specified has changed address permanently and forwarding was not applicable
I have substituted "Lastname, Firstname" and "Ourserver..." for the real values for the user.
Also, when sending mail directly to the user, the messages get through just fine with no errors, the problem is only when a message is send to a distribution list where this user is a member (seems to be all lists/groups that they are a member of). Also, all other users in the same lists get the messages with no errors, it seems to be only this one mailbox.
Thank you in advance if anybody knows of a solution to this problem. I have looked around but have not been able to find a solution for this yet.