When I try to join an internet game, I am repeatedly met with the line "Authentication Failed". I read the FAQ, and I've pretty much ruled out someone else using my key, both because it happened straight after purchase, and that I haven't told it to anyone at all...
Additionally, when I try to host a lan game, when others try to join it says "This does not appear to be a lan game" and refuses to let them connect either.
When I start the game, I DO appear to successfully auth, as it greets me with "Welcome, TTFTCUTS" at the bottom (which has not been anything else other than the generic "blockhead####" etc).
Am I doomed to never play multiplayer because I am stuck behind a university network? Or have I overlooked something silly?