when you click on "Host game" or "Join game", the game tries to reach the web server. So I guess your firewall must pops up a window asking you if you want to authorize the game to access Internet or not.
If you play in fullscreen mode, switch to windowed mode before to try to create a game or find online games.
If you're already in windowed mode, try to look for your firewall pop up.
If it's not that, then I'll need to see your "System.log" file, from your Tennis Elbow 2006's directory.
== Mana Games ==
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