Fix OneDrive Sync Blocked by Third-Party Antivirus File Lock - Fix 'Chrome Service Unavailable' Error on Mac-Windows Defender Setup Error 504 Troubleshooting

Updated 2026-06-19 07:12:55security-tools
Fix OneDrive Sync Blocked by Third-Party Antivirus File Lock - Fix 'Chrome Service Unavailable' Error on Mac-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.