Just reread and did you also forward the UDP protocol as well as the TCP, RDC needs both.
Just checked my firewall config and no, my RDP forwarding, works with TCP only. I believe RDP is encrypted though some of the keys used have entered the public domain. But RDP over VPN (or an SSH tunnel) are solid choices.
I'd endorse a previous suggestion that there is no good reason change the port in Windows, rather, use the router to forward from a different (high) public port (e.g. 53389/tcp) to the standard Windows port 3389/tcp, limiting the allowed source IPs / networks where possible.
With XP, you need to make sure that in addition to Remote Desktop being enabled, the user you want to connect as is listed in the Allowed Users and that Remote Desktop is allowed by the Windows Firewall (or any other software firewall) in addition to the router firewall. Windows Firewall needs to allow the connection from Any computer (not just local subnet) or you can specify custom source IPs / networks as above.
If you have changed the port in the Registry then the rule in Windows Firewall probably did not follow the port you chose.
Nothing needs changing with the configuration on the computer you are connecting from. Just specify the computer to connect to as public-ip:public-port
Windows Remote Desktop client has some advanced settings - such as looking for a Terminal Services gateway first, but you can turn that off to make the initial connection negotiate quicker.
prompt $P - Invalid drive specification - Abort, Retry, Fail? $G
prlzx on n e w n e t Max ADSL