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Fix Windows Update Proxy Error Permission Denied - Fix 504 Gateway Timeout in Windows Security After Update-How to Reinstall the Windows Security App (Microsoft Defender)

2026-06-14 05:56:02developer-tools
Fix Windows Update Proxy Error Permission Denied - Fix 504 Gateway Timeout in Windows Security After Update-How to Reinstall the Windows Security App (Microsoft Defender)

Final checklist

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

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