Instructions
Locate the hard drive on the Xbox 360. If your Xbox 360 is laying down, the hard drive will be located on the left hand side of the Xbox 360.
Unplug all cables attached to the Xbox 360.
Remove any memory units that may be installed on the front of the Xbox 360.
Press the "Eject" button located near the hard drive, which will free the hard drive from its locked position. Remove the hard drive.
Plug all cables back into the Xbox 360.
Restart the Xbox 360, the error code should no longer show up on the screen.
Replace the hard drive on the Xbox 360. Ensure the hard drive is firmly in place.
Restart the Xbox 360. If the error code appears again, the hard drive has become corrupted and is no longer working. You may still play on the Xbox 360 without a hard drive, although you will not be able to save games or download any materials until you replace the hard drive with a working one.