Not wanting to lose any information moving my Xbox from 20GB to 320GB I tried to follow the instructions that came with this kit. The instructions specifically remind you to use the supplied CD. When I inserted it, the Xbox wouldn't read the disc, although it looked clean with no scratches or other obvious damage. After a few attempts to use the CD, I just plugged in the cable. To my surprise, Xbox immediately popped up a message that it found a data cable and prompted me to start the transfer. I followed the on-screen instructions and completed the migration with no issues. Apparently I didn't need the CD even though the instructions for use say to use it.