Firewall Ports

[UncleFester]

That's true, but for most home users with Linksys routers and such, they we will able to play on multiple machines internally without any problems and no configuration changes.

If we knew what firewall was being used we could help. He could also just forward all traffic to the one internal machine he wants to play on, there are many solutions.

But I still get the feeling he is using a typical D-Link, netgear cable/dsl NAT style router and thinks it is the cause, but it is not.