Why do I get a keyboard error at boot screen?
Keyboard is not connected properly
Verify that the keyboard is connected correctly to the computer by turning off your computer and then disconnecting and reconnecting the keyboard to the computer.
Ensure that there are no stuck keys on the keyboard. If all keys seem okay and you have a standard desktop keyboard, turn it over and gently tap the back to dislodge any stuck dirt or hair.
Try another keyboard on the computer to verify that the keyboard has not gone bad.