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error HP
Error Code Screen Message: Keyboard Error (301, 304)
Keyboard malfunction or connection failure.
? What Causes This
Faulty keyboard hardware linkage/connection problems to main logic board.
✓ How to Fix It
Inspect keyboard contacts and replace the device if issues are present. Check system board status for further malfunctions, refer for repair as necessary.
Source: page 3 of the official manual
From the manual
This error code appears in:
HP Prodesk 600 G1 Small Form Factor PC