Windows Defender can be disabled, but you should understand what you're losing first

Windows Defender is the antivirus program built into Windows 10 and Windows 11. It runs automatically in the background and scans files when you open them. You can turn it off entirely, turn off specific features like real-time scanning, or exclude certain files and folders from scanning. The method depends on which version of Windows you have and what you're trying to accomplish.

Before you disable it, know what happens: your computer loses active protection against viruses and malware. Windows will show you a warning in the system tray that your device is unprotected. If you're disabling it to install different antivirus software, that's a reasonable choice — most people run only one antivirus program at a time. If you're disabling it because something is slowing down, there are faster options than removing all protection.

Key Takeaways

  • You can disable Windows Defender temporarily through Settings, or turn off individual features like real-time scanning without removing the whole program.
  • If you install a different antivirus program, Windows Defender usually disables itself automatically — you do not need to manually turn it off first.
  • Disabling Windows Defender leaves your computer without active antivirus protection, so only do this if you have another antivirus program running instead.
  • If Windows Defender is slowing your computer down, excluding specific folders or scheduling scans for off-hours is faster than disabling it completely.

Disable Windows Defender temporarily through Settings

This method turns off real-time protection for one hour, then Windows Defender turns itself back on. Use this when you need to install software that Windows Defender is blocking, or when you want to test whether it's causing a specific problem.

Open Settings by pressing the Windows key and typing "Settings", then press Enter. Click "Privacy & security" in the left sidebar. Scroll down and click "Windows Security". Click "Virus & threat protection". Under "Virus & threat protection settings", click "Manage settings". Toggle off "Real-time protection". Windows will ask you to confirm — click "Yes". The protection stays off for one hour, then turns back on automatically.

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

This method is available only on Windows Pro, Enterprise, or Education editions — not on Windows Home. It permanently disables Windows Defender until you reverse the setting.

Press the Windows key and type "gpedit.msc", then press Enter. If you see "gpedit.msc cannot be found", you have Windows Home and need to use the Settings method instead. Navigate to Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus. Double-click "Turn off Microsoft Defender Antivirus". Select "Enabled" and click "OK". Your computer will need to restart for the change to take effect. Windows Defender will no longer run in the background.

Disable Windows Defender through Services (all Windows versions)

This method works on any version of Windows and disables the Windows Defender service entirely. It is more permanent than the Settings method but easier to reverse than Group Policy.

Press the Windows key and type "Services", then press Enter. Find "Windows Defender Advanced Threat Protection Service" in the list. Right-click it and select "Properties". Change the "Startup type" dropdown to "Disabled". Click "explore", then click "OK". If the service is currently running, click the "Stop" button first. Restart your computer. Windows Defender will not start automatically on the next boot.

What happens when you install a different antivirus program

If you install Norton, McAfee, Bitdefender, Kaspersky, or another third-party antivirus program, Windows Defender usually disables itself automatically. You do not need to manually turn it off first. The new antivirus program detects that Windows Defender is running and either disables it or asks you to choose which one to keep.

If both programs remain active after installation, your computer will slow down significantly because they are both scanning every file. Open Settings, go to "Privacy & security" > "Windows Security" > "Virus & threat protection", and check the status. If it says "Managed by your organization" or shows a different antivirus program in control, Windows Defender is already disabled.

Re-enable Windows Defender if you disabled it

If you disabled it through Settings, real-time protection turns back on automatically after one hour — you do not need to do anything. If you disabled it through Group Policy or Services, you need to reverse the change manually.

For Group Policy: open gpedit.msc again, navigate to the same location, double-click "Turn off Microsoft Defender Antivirus", select "Not Configured", and click "OK". For Services: open Services again, find "Windows Defender Advanced Threat Protection Service", right-click it, select "Properties", change "Startup type" to "Automatic", click "explore", then click "OK". Restart your computer. Windows Defender will start on the next boot.

Alternatives if Windows Defender is slowing your computer

Before you disable Windows Defender entirely, try these faster options. Open Settings, go to "Privacy & security" > "Windows Security" > "Virus & threat protection" > "Manage settings". Toggle off "Cloud-delivered protection" — this stops Windows from sending suspicious files to Microsoft's servers for analysis, which can slow older computers. Toggle off "Automatic sample submission" for the same reason.

You can also exclude specific folders from scanning. In the same Settings window, scroll down to "Exclusions" and click "Add exclusions". Select the folders where you keep large files, video projects, or game installations. Windows Defender will skip these folders during scans, which speeds up both the scan and your everyday work. This keeps protection active for the rest of your system while removing the slowdown from the folders you specify.

Frequently Asked Questions

Will my computer get a virus if I disable Windows Defender?

Not automatically, but your computer has no active protection while it is disabled. If you visit unsafe websites, read files from untrusted sources, or open email attachments from people you do not know, the risk is much higher. Only disable Windows Defender if you have another antivirus program running instead, or if you are doing something specific and temporary that requires it off.

Can I disable just the notifications without disabling the protection?

Yes. Open Settings, go to "Privacy & security" > "Windows Security" > "App & browser control", and toggle off "Reputation-based protection" and "SmartScreen for Microsoft Edge". This stops the pop-up warnings but keeps the scanning active in the background. You will not see alerts, but Windows Defender is still protecting you.

Why does Windows Defender keep turning back on after I disabled it?

Windows automatically re-enables Windows Defender if it detects that no other antivirus program is running. If you disabled it through Settings, it turns back on after one hour by design. If you disabled it through Services or Group Policy and it keeps re-enabling, check that your third-party antivirus program is actually running — open its window and verify the status shows "Protected" or "Active".

Is it safe to disable Windows Defender if I have a router with built-in security?

No. A router's security protects your network from outside attacks, but it does not protect individual files on your computer from viruses or malware. You need antivirus software on the computer itself. A router and antivirus software do different jobs and both are necessary.