How to Reinstall the Windows Security App (Microsoft Defender)
If the Windows Security app (Microsoft Defender) is missing, won’t open, or shows errors, reinsta...
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Browse labWindows Defender Troubleshooting Guide for IT Admins
Windows Defender (Microsoft Defender Antivirus) is the default endpoint protection in Windows 10 ...
Fix Microsoft Store 'Failed to Start' Permission Denied Error
If you see "Microsoft Store failed to start" with a "Permission denied"<...
Fix Microsoft Store Access Denied with wsreset Command
If you see an 'Access Denied' error when opening Microsoft Store, the wsreset command often clear...
Fix Windows Search Authentication Failed After Password Change
After changing your Windows password, you may see an error like “Windows Search authentication fa...
Fix Windows Update Authentication Failed for Domain Users
If you're a domain user and see "Authentication failed" when checking for Windows Updates, the is...