So all this time I have had absolutely no problem with Steam, very happy with it, the launch of Half-Life 2 never happened as far as I'm concerned, and generally it has always been my friend, until today. So here I am pushing the kart and setting people on fire in TF when suddenly a box pops up and informs me that the account I'm playing on does not own the game. That's just pure BS considering I have the hardcopies of the Orange Box. Tried everything outisde of reinstalling and contacting tech support. Has this hapened to anyone before? How did you fix it?

Maybe you could try contacting the people at the Steam technical support people at Valve...Do they even have those, I don't know...But it's worth a try..

Thats a new one on me. I would bet this is a bug from their free weekends/passes they've been handing out. Contact support this definitely sounds like something you're going to need their involvement to fix.

Got it working again, just re-entered my product key and it game an error saying I've already registered my product, then told them to install TF2 again and gave me another error saying it's installed. But at least now it runs!