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How to Reset Windows Update Configuration to Default - Resolve Cloudflare 521 Error: Server Connection Refused-Troubleshooting Postman Certificate Import

2026-06-13 13:23:32developer-tools
How to Reset Windows Update Configuration to Default - Resolve Cloudflare 521 Error: Server Connection Refused-Troubleshooting Postman Certificate Import

Final checklist

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