In order to play X-Wing Vs. TIE Fighter online, you need to consider the following steps.
This is the most crucial and also most error prone part of the process. It may seem to be a complicated and tiring procedure, but don't give up. There are only a few things you have to overcome. 1. The router, 2. the personal firewall
Most people nowadays sit behind a router, which has an active firewall running that is blocking all ports from incoming connections. Most also have a local Firewall (Windows Firewall, Norton Security or whatever). Both of these have to be set up in order to play!
If you have a local firewall on your PC, like Windows Firewall or some other Security software enabled, create exceptions for
In Windows XP do that under Control Panel → Windows Firewall or Security Center (scroll down to Windows Firewall there) → Exceptions → Add Program…