Installing or replacing the optical drive - ThinkStation E20 (type 4215, 4219, 4220, 4221, 4222)
Attention Do not open your computer or attempt any repair before reading and understanding the "Important safety information" in the ThinkStation Safety and Warranty Guide that came with your computer. To obtain a copy of the ThinkStation Safety and Warranty Guide, go to Lenovo Support Website
This section provides instructions on how to replace the power supply assembly.
To replace the power supply assembly, 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.