zhizhu
Home / office-tools / Windows Defender Offline Scan Not Working After Update: Fixes - Troubleshooting 0x80073cf9 Installation Error-How to Fix Port Conflict in Windows Security Apps

Windows Defender Offline Scan Not Working After Update: Fixes - Troubleshooting 0x80073cf9 Installation Error-How to Fix Port Conflict in Windows Security Apps

2026-06-13 16:31:17
Windows Defender Offline Scan Not Working After Update: Fixes - Troubleshooting 0x80073cf9 Installation Error-How to Fix Port Conflict in Windows Security Apps

Result check

  • Keep one change per test run so you know which step helped.
  • Undo temporary changes after the issue is confirmed.