Fixed: Windows 11 Defender Keeps Turning Off

Windows 11 Defender keeps turning off? Don’t worry! This guide will let you know the various ways to solve this problem. It also comes with a way to protect your system.


by Jonna Updated on November 30, 2023

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Windows Defender on Windows 11

Windows Security is built into Windows and includes a piece of anti-malware software called Microsoft Defender Antivirus. (In earlier versions of Windows 10, Windows Security was known as Windows Defender Security Center.)

Windows 11 Defender provides the latest virus protection. Your device is actively protected from the moment you start Windows. Windows Security continuously scans for malware, viruses and security threats. In addition to this real-time protection, updates are automatically downloaded to keep your device safe from threats.

User Case: Windows Defender Keeps Turning off by Itself.

“I found that my Windows 11 Defender keeps turning off, which is very distressing to me. I turn it on, it's active for 2-3 seconds and then it goes off again. The prompt says ‘this app has been turned on and isn't monitoring your computer’. I tried manually turning on the Windows Defender service, to the same result - it just shuts down by itself.”

Windows 11 Defender Keeps Turning Off

The constant shutdown of Windows Defender in Windows 11 can put your online security at risk. There are many reasons why Windows 11 Defender keeps turning off, the main reasons are listed below.

Software Conflicts

If your Windows 11 computer has another third-party antivirus software installed, this software may conflict with Windows Defender, which may cause the built-in virus protection to be turned off or refuse to run.

✨ Errors in the current Windows system

Another probability that Windows Defender keeps turning off is an error in the Windows 11 system, which may prevent Windows Defender from functioning properly.

How to Fix Windows Defender Keeps Turning Off on Windows 11

If you are bothered by this problem, then don't worry. In this guide, we will show you various ways to help you solve the problem of Windows 11 Microsoft Defender keeps turning off. So, without any further ado, let's get started.

Solution 1. Update Windows Defender to Fix Known Issues

Usually, Microsoft provides updates to fix known issues. Therefore, if Windows Defender will not stay on, or Windows 11 Real-time protection keeps turning off, try updating Windows Defender to its latest version.

  1. Press Windows + I to open Windows Settings.
  2. Under the Privacy & security page, click on Windows Security.

Windows Security Windows 11

  1. Click Virus & threat protection, scroll down to Virus & threat protection updates, and click Protection updates.

Protection Updates

  1. Then click Check for updates. If there is any pending update, download and install it immediately.

Check for Updates

  1. Once done, restart your PC and then check if it fixes the problem that Windows 11 Defender keeps turning off.

Solution 2. Uninstall Third-Party Antivirus Software

If you install a third-party antivirus software on your computer, it will conflict with Windows Security, causing Windows 11 virus and threat protection not to work or Windows Security keeps turning off. To get rid of this trouble, go ahead and uninstall that antivirus software on your computer.

  1. Type control panel in the search bar and click the best match to run this tool.
  2. Find the Program section and click Uninstall a program.

Uninstall a Program

  1. Locate the antivirus software, right-click on it and choose Uninstall.

Solution 3. Disable “Turn off Windows Defender” via Group Policy

Sometimes, Windows Defender is turned off by Group Policy. Therefore, it may cause the problem that Windows Defender keeps turning off. Therefore, please follow the steps below to disable the "Turn off Windows Defender" option.

  1. Press Windows + R to open the Run dialog box.
  2. Type gpedit.msc and press Enter to open Group Policy Editor.
  3. Navigate to Local Computer Policy > Administrative Templates > Windows Components.
  4. In the Microsoft Defender Antivirus folder, double-click Turn off Microsoft Defender Antivirus to open a new window.

Turn off Microsoft Defender Virus

  1. Now select Disabled from the top left menu bar and click Apply > OK to save it.

Disabled Turn off Microsoft Defender Virus

  1. Once that's done, restart your computer and see if it manages to fix the problem of Windows 11 Microsoft Defender keeps turning off.

Solution 4. Disable AntiSpyware in Registry

When Windows 11 virus and threat protection keeps turning off or Windows Microsoft Defender fails to stay on, you can try enabling it in the registry by disabling AntiSpyware. The AntiSpyware service file has proven to be a long-term roadblock for Windows Defender. While you can't completely uninstall it from your computer, you can at least disable it by tweaking its registry values.

  1. Press Windows + R to open the Run dialog box. Type regedit and click OK. This can open the Registry Editor window.
  2. Paste the following path to the address bar and press Enter:
  • Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender

Windows Defender

  1. Now right-click on this Windows Defender folder, select New > DWORD (32-bit) value. Name this file DisableAntiSpyware. Then double-click it to open it and enter 0 under the Value data field.

Disable Antispyware

  1. Finally, click OK to save it and restart your computer. Once it starts, check if it solves the problem that Windows 11 Defender keeps turning off.

Solution 5. Refresh/Restart Windows Defender Firewall Service

The Windows Defender Firewall service is responsible for keeping this application running, both in the background and in the foreground. However, if there is a problem with this service, then the Microsoft Defender application will be the ultimate victim. Therefore, you should consider restarting or refreshing this service.

  1. Open Run dialog box as told before, type services.msc and click OK to open the Services menu.
  2. Scroll to the Windows Defender Firewall service, right-click on it, and select Restart. If the option is grayed out, then it is probably already running in the background. Therefore, you should consider using the Refresh option.

Refresh Windows Defender Firewall

Solution 6. Reset Windows 11 Defender

If none of the above methods solve the problem that Windows 11 Defender keeps tuning off, then your last option is to reset it to its factory default state.

  1. Type Powershell in the search box and run it as an administrator.
  2. Then type in the below command and hit Enter. It shall reset the Windows 11 Defender:
  • Get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage

Reset Windows 11 Defender

Solution 7. Run SFC Scan to Fix Corrupted System Files

When an native process of Windows, like Windows 11 Defender or Windows 11 virus and threat protection keeps turning off, corrupted system files may be a major cause. Thus, you can run an SFC (System File Checker) scan to scan and fix the corruption.

  1. Search cmd in the Windows 11 search bar, right-click Command Prompt, and select Run as administrator.
  2. Input the command below, and hit Enter.
  • sfc /scannow


  1. Wait and exit Command Prompt when the verification process reaches 100%. Then, check if your problem is solved.

Provides Additional Security for the Windows System

Microsoft Security for Windows 11 is a pretty useful tool to protect your computer from threats. When it keeps turning off, try the six methods above to help you get your computer back to normal. If you only use Windows Defender to keep your computer safe, this is not enough.

We recommend that you make regular backups of your system to prevent similar problems. Here I recommend you a free backup software - AOMEI Backupper Standard, designed for all Windows users. We cannot predict when viruses, malware and other malicious threats will attack our computers and cause problems such as data loss or system crashes.

However, if you have created bootable media and a system backup in advance, then you can use this backup to quickly restore your computer to a normal state after an attack. This software can also help you backup files and folders to avoid data loss, sync files and folders, clone your hard drive to another disk, and much more.

Follow the steps below to create a system backup to provide double protection for your computer. If you are a Windows Server user, you can turn to AOMEI Backupper Server.

  1. Download and launch AOMEI Backupper Standard. Click Backup -> System Backup.
Download FreewareWin 11/10/8.1/8/7/XP
Secure Download

System Backup

  1. This program will select system partition and boot-related partitions automatically. You just need to select a destination to save the system backup.

Select Destination

🧱 Tip: you can backup to external/internal hard drives, cloud drives, SD cards, USB flash drives, NAS and network location, etc.

  1. Then click Start Backup to backup the Windows 11 system.

Start Backup

🧱 Tips:
🎈 Options:
You can write comments for your backups, choose the compression level or set up email notifications for you when the task is completed.
🎈 Schedule Backup : This feature allows you to set the frequency of backups, such as daily, weekly, monthly, event triggers, and USB insertion. This allows you to not miss any changes to your system.
🎈 Backup Scheme: You can select Full Backup, Incremental Backup, or Differential Backup (available after upgrade to the Pro or higher version). In the Pro version, it also supports deleting old backups automatically to save your backup disk space.


This article gives you 6 solutions for the problem that Windows 11 Defender keeps turning off. Because Windows Defender is such an important part of your computer security, it is urgent to fix this problem quickly.

After fixing the problem, it is also recommended that you use AOMEI Backupper to backup your system to provide double protection for your computer. It can help you backup important files on your computer regularly. What's the hesitation? Try it out now!

Jonna · Editor
Jonna joined AOMEI in 2021 and has become a professional in the areas of computer backup and restoration, disk cloning, file synchronization, etc. She maintains a keen eye for the latest technology trends, ensuring that the information provided is always in step with industry developments.