HP ProOne 400 G1 All-in-One Hardware Reference Manual page 46

5. Set the top edge of the access panel down on the top edge of the computer chassis (1). Be sure
to align the hooks on the underside of the top edge of the access panel with the top edge of the
computer.
6. Rotate the bottom edge of the access panel down (2) and press it firmly onto the chassis until it
locks into place.
7. Tighten the captive screws (3) to secure the access panel in place.
Figure 3-37
8. Place the computer in the upright position.
9. Reconnect the power cord and external devices.
10. Lock any security devices that were disengaged when the access panel was removed.
11. Turn on the computer.
40 Chapter 3 Hardware repair and upgrade
Replacing the access panel