Windows Defender Troubleshooting Guide for IT Admins
Windows Defender (Microsoft Defender Antivirus) is the default endpoint protection in Windows 10 ...
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Browse labFix Windows Update 404 Not Found Error When Antivirus Interferes
You try to run Windows Update, but instead of the usual process, you get a 404 Not Found<...
Fix Windows Defender SSL Certificate Sync Errors
You might see a warning that Windows Defender can't update because of an SSL certificate error. T...
Fix Windows Search Error 0x80070490: Cannot Connect
If you see "Windows Search cannot connect" with error code 0x80070490, it usually means the Windo...
Windows Security App Not Opening After Update: Fixes
After a Windows update, the Security app may refuse to open—clicking the icon does nothing, or it...
Fix Windows Defender Virus Definition Update Failed
You see an error that Windows Defender virus definition update failed. This usually happens when ...