zhizhu
Home / macos-help / Fix Windows Update Cannot Connect to Network Error - Windows Defender Update Fails with 0x80070643-Windows Defender Not Opening? Here’s How to Fix It

Fix Windows Update Cannot Connect to Network Error - Windows Defender Update Fails with 0x80070643-Windows Defender Not Opening? Here’s How to Fix It

Updated 2026-06-13 19:00:08macos-help
Fix Windows Update Cannot Connect to Network Error - Windows Defender Update Fails with 0x80070643-Windows Defender Not Opening? Here’s How to Fix It
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.