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Fix Windows Security Real-Time Protection Not Working - How to Resolve Windows Update Certificate Errors-Fix Windows Defender Service Not Starting After Update

2026-06-13 15:23:16windows-fixes
Fix Windows Security Real-Time Protection Not Working - How to Resolve Windows Update Certificate Errors-Fix Windows Defender Service Not Starting After Update

Final checklist

  • Confirm that the same symptom is gone after a restart or refresh.
  • Keep the smallest working change and undo temporary diagnostic settings.