Fix 'Windows Security Failed to Start Access Denied' Error - Fix Task Scheduler 'Access Denied' When Running as Admin-How to Run Disk Cleanup After a Windows Update

Updated 2026-06-13 22:36:54developer-tools
Fix 'Windows Security Failed to Start Access Denied' Error - Fix Task Scheduler 'Access Denied' When Running as Admin-How to Run Disk Cleanup After a Windows Update
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.