Fix Windows Defender Not Opening Error 404
You try to open Windows Defender and get an error 404 – the page or resource can't be found. This...
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View listFix Windows Defender Service Not Starting (Error 404)
If you see error 404 when trying to start Windows Defender, it usually means the service executab...
Fix 'File Locked by Windows Security Cannot Delete'
You try to delete a file, and Windows tells you it's locked by Windows Security. This often happe...
Fix 'Port Already Allocated' Error After Windows Update
After a recent Windows update, you might see an error like 'port already allocated' when starting...
Fixing Windows Security Invalid Configuration: Practical Steps
You open Windows Security and see 'Invalid configuration' or the app won't start. This usually ha...
Fix Windows Security Antivirus Not Turning On
You open Windows Security and see that the antivirus is off, with no obvious way to turn it on. T...
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