Instructions
Power down your Xbox 360.
Remove all accessories from the USB ports of the Xbox 360.
Unplug the power supply from the wall and the Xbox 360. Separate the power cord from the gray brick-like power supply unit.
Plug the power cord to the back of the Xbox 360, the power supply unit and the wall socket.
Check that all cords and plugs are connected snugly.
Power on the Xbox 360.