Hello,
Thank you for posting in Q&A forum.
The following methods may help you solve the problem you are experiencing.
- In the search, type "PowerShell" When PowerShell appears, press "Run as administrator" Click "Yes" on the following prompt. Enter the following commands in the order shown.
Set-ExecutionPolicy Unrestricted
Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}
Set-ExecutionPolicy Restricted
After that, try opening Windows Security Center. It should work now.
- Open the Command Prompt: Search for "cmd" in the Start menu, right-click "Command Prompt" and select "Run as Administrator".
Run the System File Checker tool:
Enter the following command and press Enter to run:
sfc /scannow
Wait for the scan and repair process to complete. Restart the computer: Restart the computer after completion and check if Windows Defender has returned to normal.
I hope the information above is helpful.
Best Regards,
Yanhong Liu
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