To Remove The Computer Cover - Lenovo 40221GU Hardware Maintenance Manual

To remove the computer cover:

Note
For this procedure, it helps to place the computer face-down on a
soft flat surface. Lenovo recommends that you use a blanket, towel,
or other soft cloth to protect the touch screen surface from scratches
or other damage.
1. Remove any media (diskettes, CDs, or memory cards) from the drives,
shut down your operating system, turn off all attached devices, and
the computer.
2. Unplug all power cords from electrical outlets.
3. Disconnect all cables attached to the computer. This includes power
cords, input/output (I/O) cables, and any other cables that are
connected to the computer. Refer to "Locating connectors on the rear
of the computer" .
4. Remove the six screws that secure the system cover to the chassis.
Chapter 7. Replacing hardware
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