Windows 11 Virus Scan NOT WORKING

This might be of interest. (It addresses scan failures as well as crashes.)

Microsoft fixes known issue causing Windows Defender crashes
https://www.bleepingcomputer.com/news/microsoft/microsoft-fixes-known-issue-causing-windows-defender-crashes/

Hi again.

When I turned on my PC today, I noticed the same problem while running a quick scan. I read some similar reports online and checked my other PC, and the same thing happened.

I opened Windows Security and updated the "Security intelligence". Then, I restarted the PC and tested it again using the quick scan, and the problem didn't occur. Try doing this.

Open the "Windows Security" app, go to "Virus & threat protection". Under "Virus & threat protection updates", click on "Protection updates". Then, click on "Check for updates".

Then, restart (not shutdown) your PC and see if the problem has stopped occurring.

Please let me know how it goes.

Feel free to ask any questions you may have.

Hi. I'm David, and I'm happy to help you.

This behavior usually occurs when Windows Security components are corrupted, or even when system files themselves are corrupted.

I suggest doing the following:

1 = Reset Windows Security as instructed below:

1. Press "Windows + X" and select "Terminal (Admin)";
2. Type or paste the following command and press Enter:

Get-AppxPackage *Microsoft.SecHealthUI* -AllUsers | Reset-AppxPackage

3. Restart (not shutdown) your PC.

2 = If the problem persists, I suggest you use the System File Checker to repair possible corrupted system files.

1. Open Start and type cmd, right-click on "Command Prompt", and select "Run as administrator".
2. Run the following commands at the Command Prompt one at a time:

dism.exe /online /cleanup-image /scanhealth
dism.exe /online /cleanup-image /restorehealth
dism.exe /online /cleanup-image /startcomponentcleanup
sfc /scannow

Note: Pay close attention to the results of the commands. This will help you determine whether the procedure was completed successfully or if there was a problem. If you get any errors, let me know the error message that was displayed.

3. Restart (not shutdown) the PC and see if the problem is resolved.

3 = If it persists, I suggest you do the procedure below:

1. Press "Windows + X" and select "Terminal (Admin)";
2. Type or paste the following command and press Enter:

Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}

Note: Several red warnings may appear when running this command. Ignore them. It's normal.

3. Wait for the procedure to finish, and restart (not shutdown) the PC.

If the problem persists, please let me know, and I will provide another method.

Feel free to ask any questions you may have.