I've downloaded this game like a week ago, and didn't got any problem at all. I played today and now when I tried to launch the game, after login, I kept receiving this mesage:
"There was an error with this connection".
I've setted compatibility mode (XP SP3) and ran like administrator, now it works perfectly.
It was strange, because I had ran it and then, without restarting my PC there was an error. If someone get the same error, this could help.
Running on Windows 7.
(Sorry for my bad English...)