Reinstall Windows Security on Windows 11: 3 Methods to Use

Reinstalling Windows Security can be done using the command line

by Madhuparna Roy
Madhuparna Roy
Madhuparna Roy
A diploma holder in computers and with a keen interest in technology, Madhuparna is passionate about writing How-to guides and helping people solve the most intricate Windows issues.... read more
Affiliate Disclosure
  • Windows Security sometimes triggers unexpected errors, blocks some apps or it may break down due to a bug. 
  • Restarting your PC could help fix the issue sometimes, but if it doesn't, you would need to use more troubleshooting techniques. 
  • Although the app is enabled by default in Windows 11, you may need to reinstall Windows Security to fix the problem. 
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Windows 11 has its antivirus, but if it encounters issues, you might need to reinstall Windows Security on Windows 11.

In case you’re not familiar with this software, we encourage you to visit our Windows 11 Defender review and learn more about it.

If the app is still not working, reinstalling might be the only option; this is where today’s guide might come in handy.

Why is Windows Security not working on Windows 11?

If you’re having issues with Windows Security, the issue is probably caused by one of the following:

  • System files are corrupted – Since Windows Security is a core component of Windows, it won’t work if your files are corrupted. However, you can easily fix corrupted system files.
  • Related services are not running – All Windows components require certain services to run. If a certain service isn’t working, the affected component won’t work as well.
  • There’s is interference from a 3rd party antivirus – Often antivirus software will disable Windows Security in order to stop issues from occurring. Only way to get it back is to disable third-party antivirus software.
  • Windows updates are pending – If Windows update is pending install, that might prevent other components from working properly.
  • System settings are altered due to an internal glitch – System glitches are somewhat common and they can cause certain components to stop working.
  • The registry settings are modified – In case your registry settings are altered improperly, issues such as this one can occur. To fix them, you need to use Registry Editor and manually fix these issues.

In most cases, the Windows Security not working in Windows 11 issue pops up on the latest build. So, if you have recently upgraded to Windows 11, you may encounter this issue.

You can simply follow the above methods or refer to our guide on Windows security not installed on Windows 11 for more solutions.

What is Windows Security?

Windows Security is the suite that comes built-in with Windows. So, when you install Windows 11, it gets automatically installed. It proves to be one of the most effective security solutions by Microsoft.

It includes an antivirus program called Microsoft Defender Antivirus, known as Windows Defender Security Center in the older versions of Windows 10.

The app does a considerably good job in most situations with real-time protection for your PC from virus and malware attacks.

You may want to check first if the Windows Defender app is turned off and if enabling it may help fix the issue.

How do I reinstall Windows Security in Windows 11?

In this article

1. Use Windows PowerShell

  1. Right-click on the Start button and select Windows Terminal (Admin) from the menu. Open windows terminal to install windows security
  2. Copy and paste the below command in the Terminal and hit Enter: Get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackageRun command in powershell to repair and reinstall Windows Security
  3. Once the command is successfully executed and it generates the success message, exit the Terminal.

As you can see, it’s easy to reinstall Windows Security on Windows 11 using PowerShell, so be sure to try it.

  1. Navigate to the Start menu, right-click on it and select Run. Right click on Start and select Run
  2. Type in services.msc in the Run console search box and press OK to open the Service Manager. Open service manager
  3. Go to the right side, and under the Names, column look for the Security Center service. restart security center to install Windows Security
  4. Right-click on the service and select Restart.

Each time you boot your PC, the Security Center service starts running automatically.

But if it fails to run at times or gets disabled for some reason, you will be unable to open the Windows Security app on Windows 11.

Once you restart the service, check if you can open the Windows Security app now.

3. Turn on AntiSpyware from the Registry

Note icon NOTE
Before you make any changes to the registry editor, create a backup of the registry settings. This will help you recover any data lost during the process.
  1. Right-click on the Start icon and select Run to open the Run console. Right click on Start and select Run
  2. In the search bar, type regedit and hit Enter to open Registry Editor.Type regedit to open registry editor
  3. Now, navigate to the below path in the Registry Editor: Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender
  4. Next, go to the right side and double-click on DisableAntiSpyware. double click to open DisableAntiSpyware in the Registry Editor
  5. If the DisableAntiSpyware is not available, then right-click on a blank space, select New, and then select DWORD (32-bit) Value. Create new DWORD value
  6. Rename the new DWORD Value as DisableAntiSpyware. Double-click to open it. how to install Windows Security
  7. Now, the Edit DWORD (32-bit) Value will pop up. Here, set the Value data to 0. download and reinstall windows security
  8. Press OK to save the changes.

Now, close Registry Editor and restart your PC. The Windows Security app should work now.

Sometimes, changes to the registry settings can turn off the Windows Security components. These could be accidental changes by the user or by a third-party application on your PC.

For more solutions on installing Windows Security on Windows 11, follow our detailed guide on Windows 11’s Security center not opening.

Besides, if you have a 3rd party antivirus software installed and running on your system, you can temporarily disable it, to stop it from interfering.

You can now check if you can open the Windows security app on your Windows 11 PC.

Windows Security is a major component of Windows 11, and reinstalling it is simpler than you think. All you have to do is to follow the instructions from these guides.

If you managed to reinstall the software, visit our guide on best Windows Security settings and learn how to configure the software properly.

What method do you use to reinstall Windows Security? Let us know in the comments section below.