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Windows Defender Error 504 Setup Guide - Fix 'Connection Refused' Error in Windows Security for Remote Desktop-Remote Desktop Broken After Ubuntu Update – How to Fix

Updated 2026-06-18 06:22:23developer-tools
Windows Defender Error 504 Setup Guide - Fix 'Connection Refused' Error in Windows Security for Remote Desktop-Remote Desktop Broken After Ubuntu Update – How to Fix
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.