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error HP

Error Code LED blinks red twice then white two times

System shutdown due to internal power supply fault or malfunctioning hardware.

? What Causes This

Fault within the power supply unit or other internal hardware issues triggering safety protocols (e.g., short circuits, voltage drops).

How to Fix It

  1. Replace faulty components identified during diagnosis; typically starts with the power supply.
  2. Test system stability after replacement of identified faulty part.

Source: page 54 of the official manual

From the manual

Manual page 54 — HP error LED blinks red twice then white two times

This error code appears in:

HP Prodesk 600 G4 Small Form Factor PC