"This Steam account does not own this game." I've had it for 2 years wtf?

[GrimNecroWizard]

Whenever I try to play CSS, I keep getting an error saying this steam account does not own this game. The error comes up after like a round of a game. I've had the game for over 2 years and have never had this. What's going on?

 

[Wolfpup]

I'd complain to Valve/Steam and see what they say.

This is one of the reasons I don't buy games with this kind of DRM. And Steam is downright great compared to the crap the three consoles use...

I would have bought Half Life 2 over two years ago if not for Steam.