[PhilD]

Additional comment, since I asked a similar question a few weeks ago, and got it explained to me: when connecting from inside your LAN, you'll have to use the LAN IP adress of the server, not the outside IP of the router.

Here's an example: my router IP is 123.456.789.012 (yes, I know it's bogus), and my computer is 192.168.0.243 on the LAN. On my router, I setup port forwarding from, say, port 11111 to IP 192.168.0.243, port 10000.

On my home computer, the server runs on port 10000. If I want to connect to it from the same computer, I use IP 192.168.0.243, port 10000.

If some friend from outside has to connect, he'll use IP 123.456.789.012, port 11111.