HP ProBook 6555b Notebook-PC - Manual (Page 102)

To install an optical drive in the upgrade bay:
1. Insert the optical drive into the upgrade bay.
2. Tighten the upgrade bay screw.
3. Replace the battery.
4. Turn the computer right-side up, and then reconnect external power and external devices.
5. Turn on the computer.
92 Chapter 6 Drives