Fix Outlook High CPU Usage and Not Responding - How to Fix Permission Denied in Windows Activation Offline Installer-Windows Defender Setup Error 504 Troubleshooting

Updated 2026-06-14 17:25:21backup-recovery
Fix Outlook High CPU Usage and Not Responding - How to Fix Permission Denied in Windows Activation Offline Installer-Windows Defender Setup Error 504 Troubleshooting
Before changing system settings, save your work and note the exact error text so you can compare results after each step.

Extra verification checklist

  • Restart the affected app after changing permissions or configuration files.
  • Test the same workflow in a clean browser profile or a temporary user account.
  • Compare the result on another network if the error may be connection related.