Problem: Within Exchange 2010, I had a user who could send out email but they were unable to receive emails both internally and externally. This happened right after their account was comprised and used for spamming purposes. I was wondering if there was a black list for email and or Exchange 2010 was blocking incoming emails because Iâ€™m sure there were a lot of replies to the SPAM that this account.
Solution: Turns out there was an automatic rule within Outlook to delete all incoming email. This was most likely created by the perpetrator of the SPAM. Key is to always check the client side automatic rues when something like this is happening to only one user.