When I select "Local Area Network [IPX]" it says "Unable to initialize selected connection method". The game is an origonal retail version in perfect condition. Both of my machines are running on Windows XP Pro and it works fine on the other one. Battlenet and Single Player work perfect. Ive tried reinstalling and I've checked all over then net for an answer.
At first glance, I'd say you don't have the IPX protocol installed on your computer. I don't think WinXP installs it by default anyway.
To check if it is installed, right-click on "My Network Places" (on desktop) and choose "Properties". Then right-click on your Local Area Network and choose "Properties" again. In the box that lists all your protocols and services, check if there's an IPX connection.
If not, click "Install", then "Protocol", and then select IPX/SPX NetBIOS (or something similar). You'll probably need your Windows CD.