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Fix Windows Defender Connection Refused After Update - Windows Defender Login Loop Fix: Registry Edit Guide-How to Fix Windows Security 404 Error

Updated 2026-06-13 18:56:15developer-tools
Fix Windows Defender Connection Refused After Update - Windows Defender Login Loop Fix: Registry Edit Guide-How to Fix Windows Security 404 Error
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.