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critical HP

Error Code Red LED flashes 11 times

Processor incompatibility or feature lockout - the current processor does not support features previously used.

? What Causes This

Change of CPU but BIOS remains unchanged, conflicting hardware specifications.

How to Fix It

  1. Update BIOS to match new CPU capabilities.
  2. Disable unsupported features via BIOS settings if compatible with system.

Source: page 3 of the official manual

From the manual

Manual page 3 — HP error Red LED flashes 11 times

This error code appears in:

HP Compaq Pro 6300 SF Desktop