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Fix Windows Defender Threat Service Permission Denied Error - Fix Windows Defender 502 Bad Gateway: Tool Usage Tips-Troubleshoot Error 0x80073cf9 in Microsoft Store

Updated 2026-06-13 13:11:48office-tools
Fix Windows Defender Threat Service Permission Denied Error - Fix Windows Defender 502 Bad Gateway: Tool Usage Tips-Troubleshoot Error 0x80073cf9 in Microsoft Store
Likely symptom
Likely cause
Safe rollback

Verification route

  • Repeat the original action, not only a simplified test case.
  • Restart the app or reload the service after configuration changes.