So you’ve just done your update and your Xbox 360 has crashed or just has some weird errors, this would look like some type of error with the Xbox 360 update. To return to your previous version and clear the failed Xbox 360 update. With your Xbox turned off press and hold your sync up button (it’s the button that you sync you controller with). Keep holding the sync button and press the power button. Don’t let go of the sync button until the unit has fully started up. Now your failed Xbox update should now be corrected. As with all system software and hardware issues do this at you own risk.