Whats the point of a bigger HDD if you cant use it?

[dunno001]

Hmm... if I understand the original question correctly, my first guess would be an installation error on Map Pack 1. Since something went wrong, it didn't think it was installed, thus giving you an error that it couldn't find it. Second guess would be a generic hiccup that didn't properly link the game to the maps, causing it to be on the system, but not know where to look for it. The third option is the ugly one, and that would be a bad sector on the drive. Rather than returning a load error, it may have just returned a not present error. But it sounds like you have it fixed for now.