I have a friend who started playing using Steam. First night he logged onto the game fine, no problem. The following night he kept clicking on play and it said unable to connect to server. His internet worked fine, he was able to use other websites, chat applications, and played other games on Steam fine.

He tried restarting Steam, still the same message

I have another friend who is using Steam, and he logged onto to Spiral Knights fine.

Anyone have any suggestions or ideas?