Anyone outside my domain who sends me an email is getting a bounced email with the following error from Exchange:
550 550 5.1.1 firstname.lastname@example.org is not a valid mailbox (state 14).
I can't receive emails from external addresses until I send an email to one of my secondary addresses. Once I sent it to my secondary address, my primary address will start working for a while and fail again after a few hours.
We use Exchange 2003. Anyone has any suggestions on what to try?