Dell POWEREDGE C6105 - Manual (Page 185)

Troubleshooting Your System | 185
2 If the problem is resolved, restart the system, enter the System Setup
program, and check if the nonfunctioning USB ports are enabled.
3 Replace the keyboard/mouse with another working keyboard/mouse.
If the problem is resolved, replace the faulty keyboard/mouse.
If the problem is not resolved, proceed to the next step to begin
troubleshooting the other USB devices attached to the system.
4 Power down all attached USB devices and disconnect them from the
system.
5 Restart the system and, if your keyboard is functioning, enter the
system setup program. Verify that all USB ports are enabled. See "USB
Configuration" on page 54.
5 If your keyboard is not functioning, you can also use remote access. If
the system is not accessible, see "