Anything that prevents you from playing the game properly. Do you have issues playing for the game, downloading it or successfully running it on your computer? Let us know here.
I can't connect to most multiplayer servers. When I try to join it says "Couldn't establish network communication with server." Also, when I click on the server on the public games list the ping is "can't reach".
Things I've tried:
Restarting everything
Turning off firewall
Different internet connection
Different PC