If the optical drive has been changed without flashing the drive key your console will not accept the drive. "The Xbox 360 is designed so that the DVD drive works only with the particular game console it is installed in. Replacing a defective DVD drive with a replacement DVD drive does not work, since the replacement has a different DVD drive key, which the game console won't accept." from here. the only other way that I know that will work is if you swap the PCB boards. take the one from the new drive off and replace it with the one from the old one. That way the Xbox reads the old PCB board with the correct key. Of course that means that you will have to purchase an identical drive. Read some more about that on here. and more detail about it throughout this forum. If you need to know how to perform a change and getting your DVD Drive Key, this site will tell you how. Hope this helps, good luck.