bought an xbox with kinect on black friday 2010. the new slim with the kinect bundled.
bought a bunch of games including kinect sports and others. they all worked.
after a while i sold kinect sports and a few other games.
rebought a pre-owned copy of kinect sports from best buy last week. but it wont work in my x-box. the disc looks clean and no scratches. i tried all the steps of clearing the cache and removing my HD, but none of it worked. all other games work like kinect adventures and Mass Effect 3