This is the most bizarre thing I've ever seen. So, good luck Experts! Here we go.
In City A, I have a 3 Windows XP Professional PCs. 1 with remote desktop enabled and all appropriate IP and Linksys firewall port forwarding configured. I can successfully connect remotely to that PC from my office and several other locations tested.
In City B, I have 1 Windows XP Professional PC. These 4 PCs are new Dell Optiplex units. When I try to remote into the computer in City A from City B, the logon is successful, then the remote desktop freezes. If I leave it alone, I'll get the occasional "red X" like the connection dropped, but it still says open and frozen. Also, I can succussfully disconnect by clicking the X of the Remote Desktop window.
That is the problem. HOWEVER...
The computer in City B can successfully and consistently remote into any other remote computer at any other office. It only freezes when remoting into City A's PC.
I can successfully and consistenly remote into City A's PC from any location other than City B's PC.
To top it all off - I put the OLD windows 98 PC back on the network in City B, downloaded Remote Desktop Connection software and the Windows 98 PC successfully and consistently connects to the PC in City A!!
What in the world is going on here? I've hit every variable I can think of - IP addressing, Computer Names, Workgroup Names, Registry keys, XP Firewall stuff, new user/profiles, etc. It simply makes no sense. Why can I sit here at home and connect to City A? Why can the Windows 98 PC connect to City A? Yet, the Windows XP PC right next to the Windows 98 PC freezes immediately after logon to the City A PC! And don'f forget, the XP PC in City B can remote into every other office I support that uses RDP. I've tried absolutely every variable EXCEPT...
I have not tried remoting into a different PC in City A.
So try to figure this out and I'll try another PC in the morning.