- last post: 01.01.0001 12:00 AM PDT
Erm...hate to say this, man, but you're out of luck. Even if you did purchase the game legally, you can't exactly get a CD key from someone else.
I've heard of reverse keygens that take your product registration number and run it through an algorithim to get your original key, but that's useless if you've already uninstalled Halo. Besides, I'm not certain about the legal aspect of that method.
I would suggest getting in touch with M$ themselves through the number on the box to see if they'll send you a replacement disc. I've heard of one or two people actually getting a disc replacement through this method, so it may be worth a shot.
Oh, and I would edit your post before the Mods lock the topic down. You can't and shouldn't be swapping Live trials for a CD key.