You can disable Windows Defender temporarily or permanently, but understand what you're losing first

Windows Defender is the built-in antivirus program in Windows 11. Turning it off removes your real-time protection against malware, viruses, and other threats — which means your computer becomes vulnerable the moment you disable it. Most people who want to disable it are running a different antivirus program and don't want both running at once, which can slow your system down. If that's your situation, you have safer options than a full disable.

If you're certain you want to turn off Windows Defender entirely, you can do it through Settings, Group Policy (on Pro and Enterprise editions), or the Windows Security app itself. The steps differ depending on whether you want it off temporarily or permanently, and whether you're using Windows 11 Home or a higher edition.

Key Takeaways

  • Disabling Windows Defender removes all real-time protection, leaving your computer undefended against malware unless you have another antivirus running.
  • If you're installing a different antivirus program, that program usually disables Windows Defender automatically — you don't need to do it manually.
  • Temporary disables (for a single scan or installation) are safer than permanent ones and can be done through the Windows Security app in seconds.
  • Permanent disables require either Settings on Windows 11 Home, or Group Policy Editor on Pro and Enterprise editions.
  • Windows Update can re-enable Windows Defender on its own, so a permanent disable may not stay permanent.

Disable Windows Defender temporarily through Windows Security

The fastest way to turn off Windows Defender for a short time — while you install software, run a specific program, or troubleshoot — is through the Windows Security app. This is the safest approach because the protection comes back on automatically after a set time or when you restart your computer.

Open Windows Security by clicking the Windows Start button, typing "Windows Security," and pressing Enter. Click "Virus & threat protection" on the left side. Under "Virus & threat protection settings," click "Manage settings." Find the toggle for "Real-time protection" and click it to turn it off. A dialog box will ask you to confirm — click "Yes." Windows Defender will stay off until you restart your computer or manually turn it back on.

This method works on all editions of Windows 11. The protection automatically re-enables when you restart, so you don't have to remember to turn it back on.

Disable Windows Defender permanently through Settings (Windows 11 Home)

If you're running Windows 11 Home and want a more permanent disable, you'll use Settings rather than Group Policy (which Home edition doesn't include). Open Settings by pressing Windows key + I. Go to "Privacy & security" on the left, then scroll down and click "Windows Security." Click "Virus & threat protection," then "Manage settings."

Turn off the toggle for "Real-time protection." You'll also want to turn off "Cloud-delivered protection" just below it, which sends suspicious files to Microsoft for analysis. Both toggles will stay off until you manually turn them back on or until a Windows Update re-enables them.

Keep in mind that Windows Update can flip these toggles back on without asking you. If you find Windows Defender re-enabled after an update, these are the same toggles to turn off again.

Disable Windows Defender permanently through Group Policy (Pro and Enterprise)

Windows 11 Pro and Enterprise editions include Group Policy Editor, which lets you disable Windows Defender at a deeper level than Settings does. Press Windows key + R to open the Run dialog, type "gpedit.msc," and press Enter. Group Policy Editor will open.

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 disables Windows Defender across the system, not just for your user account.

This method is more resistant to Windows Update re-enabling the service, but it's not foolproof. If you later want to turn Windows Defender back on, return to the same policy, select "Not Configured," and click OK.

What happens when you disable Windows Defender

The moment Windows Defender turns off, your computer has no built-in antivirus protection. Any malware, ransomware, or virus that reaches your system will run without being detected or blocked. This is why you should only disable Windows Defender if you have another antivirus program running instead — not if you're leaving your computer unprotected.

Windows will also show a notification in the system tray (bottom right of your screen) that your device is not protected. This is a warning, not a bug. If you see this notification and you don't have another antivirus installed, turn Windows Defender back on immediately.

Additionally, some Windows features and third-party software may not work properly without Windows Defender enabled. Windows Sandbox, for example, requires it. If you disable Windows Defender and encounter errors in other programs, re-enabling it is often the first troubleshooting step.

When you don't need to disable Windows Defender manually

If you're installing a different antivirus program — Norton, McAfee, Bitdefender, Kaspersky, or others — that program usually disables Windows Defender automatically during installation. You don't need to turn it off first. The antivirus installer detects Windows Defender and handles the disable for you, then replaces it with its own protection.

Trying to run two antivirus programs at once does slow your computer down noticeably, but the solution is to let the new antivirus handle the disable, not to do it manually and then install the new program. This avoids the window of time when your computer has no protection at all.

If you've already disabled Windows Defender and want to turn it back on, use the same method you used to turn it off: Settings for Home edition, Group Policy for Pro and Enterprise, or the Windows Security app for a quick re-enable.

Turn Windows Defender back on

To re-enable Windows Defender, open Windows Security (Windows Start button, type "Windows Security," press Enter), click "Virus & threat protection," then "Manage settings," and toggle "Real-time protection" back on. This works on all editions.

If you disabled it through Group Policy, open Group Policy Editor again (Windows key + R, type "gpedit.msc"), navigate to the same policy (Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus > Turn off Microsoft Defender Antivirus), select "Not Configured," and click OK.

After you re-enable Windows Defender, it may take a few minutes to start scanning your system again. You'll see a notification in the system tray when it's active.

Frequently Asked Questions

Will disabling Windows Defender speed up my computer?

Slightly, but not noticeably for most users. Windows Defender uses minimal resources on modern computers. If you're disabling it because your system feels slow, the problem is usually something else — too many startup programs, a full hard drive, or a failing disk. Disabling antivirus protection to gain a small speed boost is not worth the security risk.

Can I disable Windows Defender if I don't have another antivirus installed?

Technically yes, but you shouldn't. Your computer will have no protection against malware. If you do this, you're relying entirely on safe browsing habits and not downloading suspicious files — which is not enough. Install a different antivirus first, or turn Windows Defender back on immediately.

Does Windows Update turn Windows Defender back on?

Yes, sometimes. Windows Update can re-enable Windows Defender even if you've disabled it. If you find it turned back on after an update and you have another antivirus running, you can disable it again using the same method. If you don't have another antivirus, leave it on.

What's the difference between disabling and uninstalling Windows Defender?

You can't uninstall Windows Defender — it's part of Windows 11 and can't be removed. You can only disable it, which turns off its protection but leaves the program on your system. If you later want protection again, you just turn it back on.

Will my computer get infected immediately after I disable Windows Defender?

Not necessarily, but the risk increases the moment protection is off. You won't get infected just from disabling it. You get infected when you visit a malicious website, download an infected file, or run untrusted software — and without Windows Defender, nothing stops that malware from running. The longer you stay unprotected, the higher your risk.