Originally Posted by
NightrainSrt4
Don't get rid of the bad drive. You need it.
If the circuit board on the original drive wasn't what was dead, you can swap that circuit board into the new drive and everything will work as normal.
Otherwise, you have to extract the key from the original drive and flash the firmware of the new drive with the old key. The key matches a key that is stored on the xbox itself. If the key on the drive does not match it, you will only be able to play dvd's and xbox live games. When you try and pop in a real 360 disk, it will throw an error, like what you probably already experienced.
Info on how to do that can be found in the usual places. Not going to link to scene sites because as much good they can be for legit uses, there is also information for other uses, and we don't need that here.
If you've already tossed the old drive, then the only thing you can do is nand dump / jtag the xbox and extract the cpu key. But you need to have a dashboard of 7371 or less. Then you can convert the cpu key into the dvd key and flash the new drive with it. Take off the jtag / go back to original nand / take off nand extractor. Then you'd be good to go.
Some punk kids sold me a 360 they said just the dvd drive was broken. Figured an easy fix, until I got it back and realized they flashed the dvd without the key. Luckily it was dash 7371, and I could get at the dvd key the hard way. Turns out the console was already banned from live anyway. Shrug, least it was only $20. Plays games offline great though. *knock on wood*