GMOD Help

Hello,

On my computer i turned on garrys mod, And created a multiplayer game,
I can play but my friends cant, So i tried portforwarding, Steam was using the ports,
So i knew it was working, But my friends still couldnt connect,
So i created new steam account, And switched on my vps,
Downloaded Dedicated Server and TF2 Dedicated Server on there,
Dedicated Server works, But i dont have the right game to connect on there,
So i try starting TF2 Dedicated Server, I fill name, Players ect in,
Click start, And an unusual error pops up, The error is:

Image of error:
http://img525.imageshack.us/img525/7128/errorob.jpg