Make sure you or your friends are not behind NAT. It is much easier to connect if you have all public IPs and not something starting with 192. There are so many ports required to be open for this game and GameSpy that it is much easier to just open them all for this game.
Do not use ALT+TAB and do not enter Windows when multiplayer is running. It will kill the connection to GameSpy servers that are needed even when you are creating server to your own computer.
Sometimes in the lobby the server just dies quietly and you need to disconnect and reconnect. You will notice this when players just stop coming to your server.
Answers & Comments
Make sure you or your friends are not behind NAT. It is much easier to connect if you have all public IPs and not something starting with 192. There are so many ports required to be open for this game and GameSpy that it is much easier to just open them all for this game.
Do not use ALT+TAB and do not enter Windows when multiplayer is running. It will kill the connection to GameSpy servers that are needed even when you are creating server to your own computer.
Sometimes in the lobby the server just dies quietly and you need to disconnect and reconnect. You will notice this when players just stop coming to your server.