Deeply integrated into Windows 11, “Windows Security” is a robust protection tool designed to safeguard your PC against viruses, security threads, and malware. To be more precise, this is your go-to destination for managing and customizing the security features on your computer.
In an age where hacking and sensational malware attacks have become the norm, Windows Security ensures shielding your device and data doesn’t cost you anything, which is a huge deal. That’s the reason why when Windows Security fails to open or stops working properly, we all want to get rid of the issue and restore the built-in antivirus tool sooner rather than later.
If that’s exactly what you are looking for, I have got you covered with the 17 most reliable solutions to fix Windows Security malfunctioning on your PC. Keep reading to…
Fix Windows Security Not Working in Windows 11 Like a Pro
So, what has crippled the Windows Security on your PC? Based on my personal experience, here are the major reasons why this issue crops up on Windows 11 –
- Misconfigurations
- Corrupted system files
- Conflicts from third-party antivirus tools
- Software bug
Taking these culprits into account, I have discussed various trusted ways to eliminate the problem and bring the security shield alive. Since these tips are secure, you can try them out without worrying about endangering your data.
1. Ensure Windows Security is Active
Is Windows Security active on your PC? Head into your Settings app to confirm whether or not you have allowed the antivirus tool to work at the desired space.
- Open Settings on your PC and navigate to Privacy & security > Windows Security.

- Select “Open Windows Security“.
- Now, make sure all protection options such as Virus & Threat Protection are enabled.
2. Restart Your PC
Why look anywhere else when you have a handy troubleshooter in the form of a simple restart? So, give it a go to flush out the temporary glitches that are harming Windows Security on your PC.
3. Check Group Policy Settings
Take a close look at the group policy settings and make sure they have not been tinkered.
- To get it done, press Win + R and type gpedit.msc.
- Then, press Enter.
- Next, head over to Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus
- Now, make sure all policies are set to “Not Configured” state.
4. Uninstall Third-Party Antivirus
Have you recently installed a third-party antivirus tool on your PC? If your answer is in the affirmative, there is a high chance that the third-party antivirus software is conflicting with Windows Security on your PC.
- To uninstall it, go to Settings > Apps > Installed apps > Find the antivirus tool and click on the triple-dot icon right next to it > Choose Uninstall in the menu.

5. Check the Security Health Service
While customizing the Windows security features, you might have accidentally disabled the Security Health Service.
- Press Win + R on your computer > type services.msc > press Enter.
- Locate Security Health Service and make sure it’s enabled.
- Additionally, be sure to set its Startup type to Automatic.
6. Check for Windows Updates
Considering the fact that frustrating software bugs do not stay away from Windows 11 for too long, it makes sense to go for the software update. Hopefully, the latest update may help troubleshoot the problem.
- Navigate to the Settings app > Windows Update > click Check for updates and go ahead to install the update.

7. Restart the Windows Security Service
Many a time, you can take control of the ill-fated Windows Security by rebooting the “Windows Security Service”.Knowing that this solution is quite effective and doesn’t jeopardize any of your media and data, I would suggest you try it out without fail.
- To do so, press Win + R on your PC > type services.msc > press Enter.
- Find the Security Center > right-click on it, and choose Restart.
- After that, you need to set the Startup type to Automatic.
8. Re-enable Windows Security Using Command Prompt
For a good many users, re-activating the Windows Security through the command prompt has worked in flushing out the issue.
- On your PC, launch the Command Prompt as Administrator and run the following command.
Set-MpPreference -DisableRealtimeMonitoring $false
9. Perform an SFC (System File Checker) Scan
The SFC (also known as system file checker) scan works like a charm in checking for and repairing corrupted or missing system files on Windows.
- On your computer, launch the Command Prompt as Administrator:
- Now, press Win + S and type cmd.
- Next, right-click Command Prompt and choose Run as Administrator.
- Next, you have to type the below-given command and press Enter:
sfc /scannow
3. Make sure to allow the scan to go through and complete without any obstruction.
4. If your Windows system file checker is able to discover any corrupt files it will attempt to repair them automatically.
5. Once the whole process has been completed, reboot your PC.
10. Perform a DISM (Deployment Image Servicing and Management) Scan
Deployment Image Servicing and Management (aka DISM) tool has long been a top-notch utility that lets you manage, repair, and service Windows images as well as installations with enhanced control.
- Open Command Prompt on your PC as Administrator.
- Then, run the below-mentioned commands one at a time and press the Enter key after each command:
In order to check the health of the system image on your Windows device –
DISM /Online /Cleanup-Image /CheckHealth
To scan for corruption on your PC –
DISM /Online /Cleanup-Image /ScanHealth
To repair the system image on your device –
DISM /Online /Cleanup-Image /RestoreHealth
Be sure to wait for the whole process to complete without any disturbance.
After the DISM scan has finished, restart your PC.
11. Repair Windows Security
Windows 11 provides a straightforward way to repair Windows Security. Save this repair tool for occasions when the stock antivirus mechanism starts throwing all sorts of tantrums and refuses to mend its ways.
- Open Settings on your PC > Apps > Installed apps.
- Locate Windows Security and click on the three-dot icon next to it.
- Select Advanced options in the menu
- Click on the Repair button and wait for a few seconds to let Windows repair the antivirus tool.
12. Reset Windows Security
If Windows Security remains dysfunctional even after you have repaired it, reset it.
- Open Settings app on your PC > Apps > Installed apps.
- Find Windows Security, hit the three-dot menu, and select Advanced options.
- Finally, click on the Reset button and confirm.
13. Reinstall Windows Security Using PowerShell
PowerShell offers a secure way to reinstall the Windows Security. As it’s exceptionally efficient and works in resolving Windows Security issues, there is no problem in bringing this solution into action.
- Open PowerShell on your Windows device as Administrator and run the following commands.
- To uninstall Windows Security –
Get-AppxPackage Microsoft.SecHealthUI | Remove-AppxPackage
- To reinstall Windows Security –
Get-AppxPackage -AllUsers Microsoft.SecHealthUI | Add-AppxPackage -ForceApplicationShutdown
- Check if Windows Security has been installed successfully –
Get-AppxPackage Microsoft.SecHealthUI
Once you have completed the above steps, reboot your PC.
14. Perform a System Scan Using Windows Defender Offline
No luck as yet? No worries! Now is the right time to perform a thorough system scan with the help of the Windows Defender Offline.
- Open Settings app > Privacy & Security > Windows Security on your PC > Virus & threat protection.
- Under the Current threats section, click Scan options.
- Now, select Microsoft Defender Offline Scan.
- Finally, reboot your PC to kickstart the thorough scan.
15. Reset Windows Security via Registry Editor
Registry Editor provides a native way to reset the Windows Security. For times when you find the built-in antivirus tool malfunctioning or unable to work on the expected lines, make sure to give a chance to this reliable method.
On your Windows device, press Win + R > type regedit > press Enter.
After that, head over to
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender
Now, you need to delete the “DisableAntiSpyware” key if it shows up here.
16. Perform a System Restore
If the Windows Security started malfunctioning after the recent update, it would be a good idea to revert to a previous restore point. Fret not! This has long been a pretty safe and reliable way to rescue your PC from a persistent issue.
- To do so, press Win + R and type rstrui > Then, press Enter.
- After that, select the preferred restore point and go through the on-screen instructions.
17. Reset Windows 11
If none of the suggested tips has worked in bringing the Windows Security back on track, reset your Windows PC:
- To get it done, go to the Settings app on your PC > System > Recovery.

- Under Reset this PC, click Reset PC.
- After that, select the “Keep my personal files” option and run through the process to reset your PC.
Wrapping up…
There you have it! Hopefully, your Windows Security has returned to life with all its glory. With several thoroughly tested solutions at disposal, I don’t see any reason why this issue won’t go away. Now, feel free to share your views about this PC guide and the solutions that have helped you get rid of the obstacle.