Removing or reinstalling the wall mount - ThinkCentre M90z
To remove or reinstall the wall mount, do the following:
Remove all media from the drives and turn off all attached devices and the computer. Then, disconnect all power cords from electrical outlets and disconnect all cables that are connected to the computer.
Place a soft, clean towel or cloth on the desk or surface. Hold the sides of your computer and gently lay it down so that the screen is against the surface and the cover is facing up.