Message Tracking on the Exchange server shows message is received from external source and then delivered to internal client but it is not being received by the user's Outlook.
It is only happening from one specific address. All other messages are fine but when it comes from this address the mail is delivered but not received.
The address contains our domain in it. e.g if our domain was company, the address is
firstname.lastname@example.org. Not sure if that could be part of the problem?
There is no rules set up on local clients outlooks and no transport rules configured on the exchange server.