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critical HP

Error Code Red LED flashes 10 times

Bad option card - incompatible or faulty expansion cards present issues with booting.

? What Causes This

Problematic peripherals like graphics cards, network controllers.

How to Fix It

  1. Remove the suspected bad option cards and try rebooting to see if they caused an issue.
  2. Once identified, replace them.

Source: page 3 of the official manual

From the manual

Manual page 3 — HP error Red LED flashes 10 times

This error code appears in:

HP Compaq Pro 6300 SF Desktop