5 Way to fix Windows defender is not turning on in Windows 10

5 Ways to fix Windows Defender is not turning on [Windows 10/8/7]

Antivirus Softwares protect PC from adware, spyware, and virus. Windows Defender is the most used antivirus program built by Microsoft. It comes with the Windows operating system. Sometimes Windows Defender stops working and fails to turn on. When users try to turn this on, error code or another message like failed to turn on appears. It is risky for running your computer without any antivirus program. 

I have compiled five solutions to fix the error Windows Defender is not turning on problem in Windows 10/8/7.

Let’s fix it.

  1. If you installed any third-party antivirus program, it prevents Windows Defender from tuning on and working.
  2. Damaged drivers or registry may prevent Windows defender from running smoothly.
  3. It may fail to load and work properly if you don’t update it.

How to Fix Windows Defender is not turning on Windows 10

Fix 1: Disable or Uninstall third-party antivirus program.

First, check if there is an antivirus program installed on your system. To check this, 

Step 1: Type control panel and open the app.

control panel

Step 2: Click on uninstall a program under the Programs category.

uninstall a program

Step 3: Check the installed program list. If you find any third-party antivirus program, click on it and click on Uninstall on the header. 

Uninstall selected program

Now try to open Windows Defender app.

Fix 2: Start Windows Defender service manually.

If Windows fails to turn it on, you can do this manually.

Step 1: Type services in the search bar and open service app, or press Windows Key + R to open Run.

Step 2: Type services.msc in the Run windows and click on OK or hit Enter

run services

Step 3: Scroll down and find Windows Defender Advanced Threat Protection Servicedouble click on it. Right-click on it and select properties

Step 4: Select Status type to automatic and then click on start

windows defender service

Step 5: Now Hit on Apply and OK.

Close the Windows and check if the problem Windows Defender is not turning on, fixed or not. If not, go to the next solution.

Fix 3: Modify Registry Editor

Before heading to the process, I recommend you to be cautious. Editing registry is a risky job. If you do some mistake, your system might get big trouble. 

Step 1: Type registry or Regedit in the search bar. Now, click on suggested Registry Editor app.


Step 2: Navigate the path on the left panel, 

Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender 

Windows defender path in registry

Step 3: Go to the right panel and double click on DisableAntiSpyware to edit it.

Step 4: In Edit DWORD (32-bit) Value window set the Value data: to “0“.

Step 5: Hit on OK and close the window. 

Now restart your computer and try to open Windows Defender app and check if Windows Defender is not turning on problem fixed. 

Fix 4: Run SFC Scan command

SFC scan finds corrupted drivers and registry and fixes it. Follow the steps:

Step 1: Type cmd in the search box and right-click on Command Prompt app.

Step 2: Click on Run as Administrator

command prompt

Step 3: Write sfc /scannow and hit Enter key.

SFC command

Step 4: After completing the scanning and fixing process, reboot your computer.

Now check if Windows Defender is not turning on problem persists. 

Fix 5: Update your Windows 10/8

Windows update tool scans if there is any update for Windows defender. 

Step 1: Press Windows Key + I to open settings or click on the Start icon and select Settings on the left panel.

Step 2: Click Update & Security

update and security

Step 2: Click on Windows Update on the left panel.

Step 3: Now click check for updates to find updates. Make sure you are connected to an Internet connection. 

check for updates

Now restart your pc to make changes and check if the issue “Windows Defender is not turning on” continues. If your problem still persists, refresh your PC. To refresh follow the method: Settings>Update and security>Recovery>Refresh your PC.

FAQ on Windows Defender is not turning on

Do I need antivirus if I have Windows Defender?

The updated Windows defender is a very good Antivirus program. For a normal user, it is enough to protect. If you want more protection on your data, you can install third-party antivirus program.

How to secure Web Browser from attack?

1. Keep browser updated.
2. Install Security plugin, such Avast, Avira.
3. Use 64 bit web browser.

How to Scan a Computer with Windows Defender?

.1. Open settings app by pressing Windows Key + I.
2. Go to Update & Security.
3. Click on Windows security on the left panel.
4. Click on Windows security, new app will be opened.
5. Click on quick scan or run full scan.


You have learned how to protect your pc and how to fix errors In the Windows security app. Let me know which solution works for you. If you face any problem or issue on your pc, comment below.

Next read:

Sharing is Caring

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *