If the Windows Security app isn't working correctly, in this guide, I'll explain what you can do to fix it.
Windows Security app reset (Image credit: Mauro Huculak)On Windows 11 (or 10), the Windows Security app provides a central dashboard to manage and configure many security features available with the operating system, such as Microsoft Defender Antivirus, Device Security, and Firewall.
If the app doesn't start correctly, constantly crashes, or shows an error, you can reset it to resolve most issues through the Settings app and PowerShell. However, the instructions will be slightly different depending on whether you have a Windows 10 or 11 computer.
In this how-to guide, I will walk you through the steps to repair problems affecting the Windows Security app on your computer.

On Windows 11, you can use the Settings app and PowerShell to fix problems with the Windows Security app.
From Settings appTo fix problems with the Security app on Windows 11, use these steps:
1. Open
Settings.
2. Click on
System.
3. Click the "
System components" page on the right side.
(Image credit: Mauro Huculak)4. Click the three-dot menu button next to the Windows Security app.
5. Choose the "
Advanced options" setting.
(Image credit: Mauro Huculak)6. (Option 1) Click the
Repair button to reset the app without losing the app's data.
7. (Option 2) Click the
Reset button to reinstall the app.
(Image credit: Mauro Huculak)•
Quick note: In my experience, this option doesn't delete the app's manually configured settings.
8. Click the
Reset button again.
Once you complete the steps, you should be able to relaunch the app without issues.
From PowerShellTo reset the Security app with PowerShell on Windows 11, use these steps:
1. Open
Start.
2. Search for
PowerShell, right-click the top result, and choose the
Run as administrator option.
3. Type the following command to reset the app and press
Enter: Get-AppxPackage *Microsoft.Windows.SecHealthUI* | Reset-AppxPackage
(Image credit: Mauro Huculak)After you complete the steps, the PowerShell command will reset the app to resolve any issue.
In the command, I'm using the "Get-AppxPackage" to grab the app, and the "Reset-AppxPackage" instructs the system to reset the application.

On Windows 10, you can also use the Settings app and PowerShell, but the instructions will be slightly different.
From Settings appTo repair the Security app on Windows 10, use these steps:
1. Open
Start.
2. Search for
Windows Security, right-click the top result, and choose the
App settings option.
(Image credit: Mauro Huculak)1. Click the
Reset button to reinstall the app.
(Image credit: Mauro Huculak)Once you complete the steps, the reset process should fix the most common problems with the Windows Security app.
From PowerShellTo reset the Security app on Windows 10 through PowerShell, use these steps:
1. Open
Start.
2. Search for PowerShell, right-click the top result, and choose the
Run as administrator option.
3. Type the following command to reset the app and press
Enter: $manifest = (Get-AppxPackage *Microsoft.Windows.SecHealthUI*).InstallLocation + '\AppxManifest.xml' ; Add-AppxPackage -DisableDevelopmentMode -Register $manifest
(Image credit: Mauro Huculak)After you complete the steps, the PowerShell command will reset the app to resolve any issue.
Although Windows 10 doesn't include the "
Reset-AppxPackage" option, you can use the "
Add-AppxPackage" option to register the Windows Security app.
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