Windows Defender Service Troubleshooting Checklist
If Windows Defender won't start, won't update, or shows error messages like "Service stopped" or ...
Checklists for software errors, setup, and tool workflows.
1. Reproduce
2. Isolate
3. Apply
4. Verify
Latest checklists
View listFix Windows Defender File Locked During Scan
You run a Windows Defender scan and it reports that a file is locked and can't be scanned. This i...
Fix Windows Search Permission Denied Error
You open the Start menu or File Explorer, type a search query, and get a 'Permission Denied' erro...
Fix Windows Activation SSL Certificate Error After System Restore
After performing a system restore, some users encounter an SSL certificate error when trying to a...
Fix PowerShell Auto Start Not Working Due to Execution Policy
You set a PowerShell script to run automatically at startup, but it fails silently. The script wo...
Microsoft Store Offline Installer Not Working on Windows 10: Fixes
You downloaded the Microsoft Store offline installer (an .appxbundle or .msixbundle file) to inst...
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