The wireless keyboard and mouse are not working.

1. Plug in the USB receiver properly

Check if the receiver under the mouse has been taken out and plugged into the computer's USB port.

2. Check batteries / charging
If the batteries are dead, replace them with a new pair of batteries.

3. Check if the switch is turned on
There is usually an ON/OFF switch at the bottom of the keyboard/mouse, toggle it to ON.

4. Change the USB port position
Replace the port of the USB receiver to see if the port is faulty.

5. Restart the computer

Simple but effective, to rule out system driver crashes.