Disable Windows Defender temporarily through Settings

The fastest way to turn off Windows Defender for a few hours is through the Windows Security app. Open Windows Security (search for it in the Start menu), select Virus & threat protection, then click Manage settings under "Virus & threat protection settings". Toggle Real-time protection to off. Windows Defender will stop scanning files and programs when ready.

This method works for most situations — installing software that triggers false alarms, running older programs that conflict with the scanner, or testing whether Defender is slowing down your system. The protection stays off until you toggle it back on, or until your computer restarts. If you restart before re-enabling it, Windows will turn Defender back on automatically after a few minutes.

You need administrator rights to make this change. If you do not have admin access on your computer, you will see a lock icon next to the toggle and cannot change it without a password.

Key Takeaways

  • Real-time protection can be toggled off in Windows Security settings and stays off until you restart or manually turn it back on.
  • Disabling Defender through Settings is safer than using Group Policy or Registry edits because the change is reversible and visible.
  • Windows automatically re-enables Defender after a restart, so you do not have to remember to turn it back on.
  • Some software installations or system troubleshooting genuinely require Defender off, but turn it back on as soon as you finish.
  • If you cannot access the toggle, your computer is set to administrator-only, and you will need the admin password.

Why Windows Defender turns back on after restart

Microsoft designed Windows to re-enable Defender automatically if it detects the protection is off. This happens a few minutes after startup, even if you disabled it through Settings. The system treats a disabled antivirus as a security risk and corrects it without asking.

This automatic re-enabling is intentional — it prevents someone from disabling protection and forgetting to turn it back on. If you need Defender off for longer than one session, you have to disable it again after each restart. For most temporary situations (installing one program, running one test), you only need to disable it once.

Disable Defender using Group Policy (Windows Pro and Enterprise only)

If you use Windows Pro, Enterprise, or Education edition, you can use Group Policy to disable Defender more completely. Press Windows key + R, type gpedit.msc, and press Enter. Navigate to Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus. Find the policy called Turn off Microsoft Defender Antivirus and set it to Enabled.

This method disables Defender even after restart, unlike the Settings toggle. However, Group Policy is not available in Windows Home edition — only Pro and above have it. If you try to open gpedit.msc on Home edition, you will get an error message.

After you finish what you needed to do, return to the same policy and set it back to Not Configured or Disabled to re-enable Defender. Leaving it off permanently leaves your system unprotected against malware.

Turn off Defender notifications without disabling protection

If Defender is slowing you down or interrupting your work with notifications, you do not have to disable the whole program. You can turn off just the notifications while keeping real-time protection running. Open Windows Security, go to Virus & threat protection > Manage settings, and scroll down to Notifications. Toggle off Show notifications.

This keeps Defender scanning and protecting your system in the background, but you will not see popup alerts or see it in the system tray. Defender still logs what it finds, so you can check the protection history later if you want to see what it blocked. This is a good middle ground if you trust Defender to work without constant feedback.

What to do if you cannot disable Defender

Some computers are locked down by an organization or administrator. If the toggle in Windows Security is grayed out or locked, your system is managed by Group Policy or a mobile device management tool. You cannot override it without the administrator password.

Contact your IT department or the person who manages your computer. They can temporarily disable Defender on their end, or they can whitelist the program you need to run so Defender stops blocking it. Do not try to work around the lock by editing the Registry or using third-party tools — that usually makes the problem worse and can trigger security alerts.

Defender stays off only until you restart — plan accordingly

Because Windows re-enables Defender automatically after restart, you need to finish what you are doing before you shut down or restart your computer. If you disable Defender, install software, and then restart without re-enabling it, Defender will turn itself back on during startup. You will have to disable it again if you need to continue.

For longer projects that require Defender off, use Group Policy (if you have Pro edition) instead of the Settings toggle. Group Policy keeps Defender off across restarts until you change the policy back. Just remember to re-enable it when you are done.

Frequently Asked Questions

Will my computer get infected if I disable Windows Defender?

Not when ready, but you lose real-time protection while it is off. Malware can install if you read or run infected files during that time. The risk is low if you disable Defender for a few minutes to install trusted software, but high if you leave it off while browsing untrusted websites or downloading files from unknown sources.

Can I disable just the firewall instead of the whole antivirus?

Yes. Windows Defender includes both an antivirus scanner and a firewall. In Windows Security, go to Firewall & network protection and toggle off the firewall for the network type you are using (Domain, Private, or Public). You can disable the firewall while keeping the antivirus scanner on, or vice versa.

What if a program says Defender is blocking it but I cannot find the notification?

Check the protection history in Windows Security. Open Windows Security, go to Virus & threat protection, scroll down, and click Protection history. You will see everything Defender blocked or quarantined. If your program is there, you can restore it or add it to the exclusions list so Defender stops blocking it without disabling the whole program.

Does disabling Defender affect Windows Update?

No. Windows Update runs independently of Defender and will continue to read and install updates even if Defender is off. Disabling Defender does not affect system updates, driver updates, or any other Windows maintenance.

Can I uninstall Windows Defender completely?

No. Windows Defender is built into Windows and cannot be uninstalled. You can disable it or replace it with a third-party antivirus, but the Defender files will remain on your system. If you install another antivirus, Defender usually disables itself automatically to avoid conflicts.