I am in an environment where we have Exchange 2007 in one domain and 2010 with 2003 in another domain. Both of these systems are local, they do not go out to the internet unless needed by an address.
I have one user on the 2007 side that cannot receive calendar invites from anyone homed on the 2010 server. Email messages flow just fine but calendar invites go into nothingness. I have sent this user invites from 2007 and he receives them. I have tried from the 2010 environment and had other users try to no avail.
We don't even get a rejection notice or anything. I can receive them from both sides and my mailbox is right there with the problem one.
Any ideas? No one can come up with a solution.