we have exchange server 2003 , and we send email to a certain recipient in an external domain. He receives emails from all of us but from one user (lets say user A).
UserA gets "..'You do not have permission to send to this recipient'
but he was able to send emails to this recipient without any issue. It all started suddenly.
The external email address is not disabled and receives email from our company just fine (except from userA).
UserA can send email anywhere else just fine.
Any ideas ?