Fix Windows Defender Service Error 577: Step-by-Step - Fix OneDrive Sync Stuck on 'Processing Changes'-Troubleshooting Firefox Not Responding on New Tab

Updated 2026-06-17 21:34:27cloud-software
Fix Windows Defender Service Error 577: Step-by-Step - Fix OneDrive Sync Stuck on 'Processing Changes'-Troubleshooting Firefox Not Responding on New Tab
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.