In order to use FS2NetD, the community's replacement for PXO, you need to have one of the latest builds of The Freespace 2 Source Code Project installed. In order to use FS2NetD you'll need to follow the following steps:
1) Firstly you'll need to download the latest version of Freespace Open, currently this can be found here. When the installer has downloaded, run it and let it guide you through the installation process.
2) Now that you have FS2 Open installed you will need the Multiplayer Config File. Once you have downloaded that place it in your main Freespace 2 directory, NOT your Data folder.
3) Next you'll need to register an FS2NetD account, to find the registration form go here. When your account is registered load FS2 Open, go to Multiplayer Options and replace the PXO login information with your new FS2NetD username and password.
4) Finally go to your main Freespace 2 directory and delete speffects.vp and zpack.vp. These are not supported by multiplayer and you will encounter "Hacked tables" errors if you do not remove them. Then go into your \data\tables directory and delete ALL files from here.
5) Load up Freespace 2 Open, select your Multiplayer pilot and join a game. Have fun flying!
NOTE: Currently Freespace Open Multiplayer has no lobby like the one PXO used. Therefore when you login you will be taken straight to the games screen. Until a lobby is created you may use our IRC channel to find players (server: irc.maxgaming.net port: 6667 - channel: #SSX) if you don't have an IRC client you may use the we based client that we have provided for free here: Free IRC Client.