Windows Defender is the default antivirus that ships with Windows 10. You don’t have to do anything to set it up; just starting using Windows 10 and it’s already working in the background automatically and comprehensively protecting your computer from all the different types of malware that are threats to your computer: viruses, worms, trojan horses, spyware, and other rogue security software.

For more on Windows 10 threats and to understand exactly what they are, see: How to prevent and remove viruses and other malware

Throughout Windows’ history, Microsoft preferred to defer antivirus protection to third-parties, so it was common to use antivirus from a company that wasn’t owned or operated by Microsoft. Windows Defender originally began as just spyware protection; however, with the release of Windows 10, Windows Defender was now a full-fledged antivirus solution and one that is optimized by Microsoft to run seamlessly in the background while you use your computer.

There are still plenty of third-party antivirus software programs out there if you want them, but most experts agree that Windows Defender is all you need to stay safe online.

When you buy a computer, you may find that it comes with third-party antivirus already. This happens when manufacturers make deals with antivirus companies—Dell computers, for instance, can often be found with McAfee security. If you have an antivirus program running on your computer already, then Windows Defender won’t be running, as you can only have one antivirus program running at once. But there’s nothing you need to do here: Windows Defender will automatically disable itself when it detects another antivirus program is running. Likewise, when you uninstall an antivirus program from a third-party such as McAfee, Windows Defender will automatically start running. You can double check that by clicking on the Windows Defender icon from the notification tray in the taskbar.

While third-party antivirus solutions may do a great job at protecting your computer, they can sometimes run “heavy” on your machines. If you’re noticing too much fan noise or it seems like your hardware is getting too much of a workout, try making the switch to Windows Defender and you should no longer have any problems.

The following tutorial demonstrates how to turn on or off the Windows Defender antivirus protection when you’re using a version of the Windows 10 operating system.

How to Turn On/Off Windows Defender in Windows 10

If you don’t want to only leave it up to Windows 10 when your Windows Defender antivirus turns itself on and off, you can also disable it manually from the Local Group Policy Editor. Here is how you can turn Windows Defender on and off from the Group Policy settings in Windows 10:

Notes:

  • You must have one of the following editions of Windows 10 to be able to use the Local Group Policy Editor: Windows 10 Pro, Windows 10 Enterprise, or Windows 10 Education.
  • Starting from Windows 10 version 1703, Windows Defender is not integrated into the Windows Security app. Read more: Windows Defender Antivirus in the Windows Security app

1. Open the Local Group Policy Editor app.

2. From Local Group Policy Editor’s left pane, navigate through to the following folders:

Computer Configuration\Administrative Templates\Windows Components\Windows Defender Antivirus

3. From the right pane with Windows Defender Antivirus selected, double-click on Turn off Windows Defender Antivirus to change its policy settings.

4. From the Turn off Windows Defender Antivirus policy window, choose between Not Configured (to turn on Windows Defender), Enabled (to turn off Windows Defender), and Disabled (to turn on Windows Defender) and then click OK to save the policy changes.

You can now close the Local Group Policy Editor and continue using your computer if you like.

That’s all.