Windows Defender Failed to Start: Manual Malware Check Guide - Windows Security Service Not Starting at Boot Fix-How to Solve SSL Certificate Error in Windows Search
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.