In our Exchange2k7-Outlook environment : Whenever we send a mail out to let's say "email@example.com" we do not receive the "user does not exist" DSN return message.
When I use message tracking on our Edge server it shows a record with the following :
Eventid : DSN
SourceContext : Failure
MessageSubject : undeliverable *subjecthere*
Why does it say Failure ? I have no idea where to look next.