Windows Defender can be disabled, but doing it permanently requires multiple steps across different settings

Windows Defender is built into Windows 10 and Windows 11 and runs by default. You can turn it off through Settings, but the system will re-enable it automatically after a period of time — usually within 24 hours — unless you also disable the security service that manages it. Completely disabling Windows Defender means stopping both the real-time protection toggle and the Windows Security service itself, then preventing Windows Update from turning it back on.

The reason this matters: if you install a third-party antivirus program, Windows Defender will conflict with it. Both programs try to scan files simultaneously, which slows your system and can cause crashes. If you are replacing Windows Defender with another security tool, you need to remove it entirely rather than just hiding it.

Key Takeaways

  • Disabling Windows Defender through Settings alone is temporary — the system will re-enable it within 24 hours unless you also stop the underlying service.
  • You must open Services (services.msc) and set Windows Defender Service to "Disabled" to prevent automatic restart.
  • Group Policy Editor (gpedit.msc) on Windows Pro, Enterprise, or Education editions allows you to lock the setting so Windows Update cannot override it.
  • Home edition users cannot access Group Policy, so the service will eventually restart after major Windows updates.
  • Completely removing Windows Defender requires uninstalling it through PowerShell or a third-party removal tool if you want it gone permanently.

Disable real-time protection in Windows Security

Open the Windows Security app by typing "Windows Security" into the Start menu search. Click "Virus & threat protection" in the left sidebar, then click "Manage settings" under "Virus & threat protection settings."

Toggle off "Real-time protection." Windows will ask for administrator permission. Click "Yes." This stops Windows Defender from actively scanning files as they open or read, but the service itself remains running in the background. Within 24 hours, Windows will turn this back on automatically.

Stop the Windows Defender Service through Services

Press Windows Key + R to open the Run dialog. Type services.msc and press Enter. This opens the Services window, which lists every background service running on your computer.

Scroll down to find Windows Defender Service (it may also appear as "WinDefend"). Right-click it and select "Properties." In the Startup type dropdown, change it from "Automatic" to "Disabled." Click "explore," then click the "Stop" button to stop the service when ready. Click "OK" to close the window.

This prevents Windows Defender from starting when your computer boots. However, Windows Update can still re-enable this service after major updates, especially on Home edition.

Lock the setting with Group Policy (Pro, Enterprise, Education only)

If you use Windows Pro, Enterprise, or Education edition, you can prevent Windows Update from re-enabling Windows Defender. Home edition does not have access to Group Policy.

Press Windows Key + R and type gpedit.msc, then press Enter. Navigate to Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus. Find the policy called "Turn off Microsoft Defender Antivirus" and double-click it. Select "Enabled" and click "OK."

This locks Windows Defender off at the system level. Even if Windows Update runs, it cannot re-enable the service because Group Policy overrides it. You can reverse this at any time by returning to the same policy and selecting "Not Configured."

Completely uninstall Windows Defender (permanent removal)

If you want Windows Defender removed entirely rather than just disabled, you can uninstall it through PowerShell. Open PowerShell as administrator by right-clicking the PowerShell icon and selecting "Run as administrator."

Type the following command and press Enter:

Uninstall-WindowsFeature Windows-Defender

Windows will remove the Windows Defender files and service. Your computer will restart. After restart, Windows Defender will no longer appear in Windows Security or Settings.

On Home edition, this command may not work because Home edition does not allow removal of built-in features. In that case, you can use a third-party uninstaller tool like O&O AppBuster or Winaero Tweaker, which can force removal of Windows Defender. These tools modify system files, so use them only if you are comfortable with that level of change.

What happens after you disable it

Once Windows Defender is disabled, your computer has no built-in antivirus protection. If you are disabling it to install a different security program, install that program when ready after disabling Windows Defender. Do not leave your computer unprotected.

Windows will display a notification in Settings that your device is not protected. This is accurate — you are responsible for installing replacement protection. If you change your mind, you can re-enable Windows Defender by reversing these steps: open Services, set Windows Defender Service back to "Automatic," or disable the Group Policy rule you created.

Why you might want to keep Windows Defender instead

Windows Defender has improved significantly in recent versions. Independent testing labs like AV-TEST and AV-Comparatives rank it alongside paid antivirus programs for detection rates. It uses less system memory than many third-party options, and it integrates with Windows Update so you always have the latest threat definitions.

If your reason for disabling it is performance, try disabling scheduled scans instead of the entire program. Open Windows Security, go to "Virus & threat protection," click "Manage settings," scroll down to "Exclusions," and add folders you use frequently (like your Documents or Downloads folder). This lets Windows Defender run without scanning those folders, freeing up resources while keeping protection active.

Frequently Asked Questions

Will my computer be slower if I disable Windows Defender?

Yes, initially — but only because you no longer have antivirus protection running. If you install a replacement antivirus program, the performance impact depends on which program you choose. Some third-party antivirus tools use more system resources than Windows Defender, not less. If performance is your concern, test Windows Defender with exclusions before removing it.

Can I disable Windows Defender on Home edition permanently?

You can disable the service, but Windows will re-enable it after major updates because Home edition lacks Group Policy. To keep it disabled permanently on Home edition, you must uninstall it using a third-party tool like O&O AppBuster, which carries the risk of system instability.

What if I disable Windows Defender and then install a new antivirus program?

Install the new program when ready after disabling Windows Defender. Most antivirus installers will detect Windows Defender and offer to remove it as part of their setup. If they do not, follow the uninstall steps above. Never run two antivirus programs simultaneously.

How do I turn Windows Defender back on if I change my mind?

Open Services (services.msc), find Windows Defender Service, right-click it, select Properties, change Startup type back to "Automatic," and click "Start." If you used Group Policy, open gpedit.msc, navigate to the same policy, and select "Not Configured" instead of "Enabled."

Does disabling Windows Defender affect Windows Update?

No. Windows Update will continue to run and install patches. On Pro and Enterprise editions with Group Policy enabled, Windows Update cannot re-enable Windows Defender because the policy blocks it. On Home edition, major updates may re-enable the service.