I have a client running Windows Small Business Server 2003. For reasons too dull to explain, they would access this machine via Terminal Services using the domain mail.foo.com (where "foo" represents the company's domain name). Because I moved their mail to Google Apps (and other reasons), we had to change this domain name to something else: server.foo.com.
The users cannot connect to the server using server.foo.com. They must connect using the IP address of the server, even though the domain points to that very same IP address. In fact, I have verified this by pinging that domain, copying the resulting IP address from the ping results, and connecting to the server using RDC. It works fine!
Why can they connect using the IP address but not the domain name, even though they are one and the same? I don't get it.