HP Pavilion Slimline s5220f Supplementary Manual page 15

6 Lay the computer on its side.
7 Insert the bottom of the side panel into the slots in the
computer rail, and then swing the panel down onto
the computer.
8 Slide the panel toward the front of the computer until
there is no gap.
— Removing and Replacing the CD/DVD Drive
537495-001
9 Set the computer upright.
10 Tighten the side panel thumbscrew on the back of the
computer.
7