Networks

Ok, I've read dozens and dozens of posts about this but've yet to get it to work, here are the details:

.trying to connect to a File Server running windows 2003 SBS server using remote desktop
.was able to connect to it from outside/inside the LAN (server has fixed IP address)
. after a security update I wasn?t able to connect
. purchased 5 TS User CAL?s and installed them on the server
. still cannot connect, message "This computer cannot connect to the remote computer, try connecting again. If the problem persists contact the remote computer owner or with the network admin"
.All along I HAVE been ABLE to connect using realVNC software but this doesn?t solve my problem since I need to log in to the server using independent sessions
. tried Firewall up and down NO RESULTS
. PING responds

PLEASE HELP!!!!!