• Make sure the keyboard/mouse is firmly plugged into the back of the computer
• Try unplugging one or both, and then reinserting it into the back of the computer
• Try plugging your USB keyboard/mouse into a different USB socket
• Replace the keyboard/mouse with one that you know works
• If you cannot see any lights on your keyboard when you press the Caps Lock or Num Lock key, it may be a dead keyboard
• Make sure there is no dirt or fluff clogging up either the optical laser or roller ball on the underside of your mouse. It may require a clean
• If you are using a wireless keyboard/mouse, try pressing the reset button on the device or replace the batteries.