I am rolling out Exchange 2010 in an environment that has Exchange 2003 already installed. The goal is to co-exist for a few weeks while we migrate the users from the Exchange 2003 server.
I created a user in the Exchange 2010 server and I can send to users in the Exchange 2003 server. I can also send to the internet from the Exchange 2010 user.
However, I cannot send from the Internet or the Exchange 2003 user back to the Exchange 2010 user. They just pile up in my queue.
What am I missing here?