Fix Windows Security Service Not Running for Antivirus
If Windows Security shows 'Service not running' or your antivirus isn't working, the underlying s...
Checklists for software errors, setup, and tool workflows.
1. Reproduce
2. Isolate
3. Apply
4. Verify
Latest checklists
View listFix Windows Defender Virus Definition Update Failed
You see an error that Windows Defender virus definition update failed. This usually happens when ...
Fix Windows Defender Threat History Not Loading Due to Timeout
When you open Windows Security and click on 'Threat history', you might see a spinning circle fol...
How to Reinstall Windows Defender After Error 404
If you see a 404 error when trying to open Windows Defender, it usually means the app's files are...
Windows Security App Not Working After Update: Fixes
After a Windows update, the Windows Security app may fail to open, show a blank screen, or displa...
Fix Windows Activation Error After Hardware Change
You've just swapped out your motherboard, CPU, or other major hardware, and now Windows shows an ...
Topic paths
Quick titles
How to Fix Windows Defender Rate Limit Exceeded ErrorFix BitLocker Error 0x8031004a on Windows 10/11How to Fix Command Prompt Permission Denied in Safe ModeFix 'Microsoft Store Module Not Found' Error on ReinstallHow to Solve pip Permission Issues on MacTroubleshoot Command Prompt Settings That Won't SaveWindows Search Not Working After Latest Update: FixesHow to Fix 502 Bad Gateway in Windows Search