Cant Access Remote Desktop to Server added to Domain? Help!

I have two servers on a network. The main server is an SBS2003 server and is the PDC. I had a second server on the network but not a part of the domain. IT is running Server 2003 standard that I was able to connect to using remote desktop. I needed to add a MS Exchange deployment/management tools to the second server. So, I got the SBS Exhange disk 2 and went to try and add the management tool. The problem was that it said the computer had to be a part of the domain. Once I added the computer to the SBS domain, I can no longer access it using remote desktop. What happened and how can it be fixed?