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 Microsoft Store Permission Denied Error
You try to install or update an app from the Microsoft Store and get a 'permission denied' error....
Fix Chrome Profile Version Mismatch Sync Error
You see a message like "Profile version mismatch" in Chrome and your bookmarks, ...
Fix Windows Security High CPU Usage: Step-by-Step
If you notice your PC fan spinning loudly or sluggish performance, Windows Security might be usin...
Fix Microsoft Store Error: Port Already Allocated After Update
After a Windows update, you might see a Microsoft Store error saying a port is already allocated....
Fix Microsoft Teams DNS Error After Update
After a Microsoft Teams update, you may see a DNS error preventing sign-in or connection. This us...
Topic paths
Quick titles
OneDrive 404 Error: Quick Fix GuideRecover BitLocker Key from Event Viewer LogsPowerShell Command Missing After Windows UpdateTroubleshoot Microsoft Store Sync FailureTroubleshoot Nginx Permission Denied on LogsCut Down Command Prompt Memory UsageFix Outlook Cache Folder Permission Denied ErrorHow to Fix Teams No Audio Device Detected