I have used the same Exchange server for over 2 years. I have one server that delivers approximately 800 emails per day to me. With all of these emails, it is imperative they be delivered.
Approximately 2 months ago, I started using a new mail host. I moved my MX records to the new server.
Ever since that time, 1/2 of my mail goes to the new server, 1/2 to the old. I have kept the old server up in case something like this happened. But after a month, shouldn't it have ceased?
Am I hurting the situation by leaving the previous path open?
If I have the new server reject all incoming mail, will the delivering server go peek at the MX record and see that it is changed? Could I have missed something BIG?