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Is Microsoft Defender, formerly Windows Defender, inactive on your PC? Turning on Defender in Windows Security is easy, but sometimes other programs can stop it from running. This How.com.vn guide will show you how to turn on Microsoft Defender on your Windows 10 or 11 PC and help you troubleshoot errors along the way.
Things You Should Know
- To turn on Defender, open Windows Security and select "Firewall & network protection." Choose the active network, then enable "Microsoft Defender Firewall."
- If Microsoft Defender won't turn on, you may have another antivirus program running. Uninstalling it should fix the problem.
- If you're using a work computer, you may need to turn on Defender using Group Policy Editor.
Steps
Turning on Microsoft Defender
- Open your Windows Settings. A fast way to get there is to right-click the Windows menu in the taskbar and select Settings. You can also click the gear icon in the Windows menu.
- If Microsoft Defender has turned itself off, it's usually because there's another antivirus or antimalware program on your PC. Try this method first to enable Defender—if it doesn't turn back on, or if you've seen an error that says "The Service Couldn’t Be Started" or " Windows Defender is turned off by group policy," see the Troubleshooting section.
- Open your Firewall & Network Protection settings. The steps are a little different depending on your version of Windows:
- Windows 10:
- Click Update & Security.
- Click Windows Security in the left panel.
- Click Firewall & network protection.
- Windows 11:
- Click Privacy & Security in the left panel.
- Click Windows Security at the top of the right panel.
- Click Firewall & network protection.[1]
Advertisement - Windows 10:
- Select the active network. You can enable or disable Microsoft Defender for different networks, which can be useful if you use your computer at work and home. To turn on Defender for the current network, click the network that's labeled "Active."
- Toggle "Microsoft Defender Firewall" on. If the switch is turned off, clicking it should turn on Microsoft Defender.
- If you're connected to a network at work or school, the admin may be using a different security method on the network and may not allow you to turn on Microsoft Defender.
Community Q&A
- QuestionHow do I disable Windows Defender on Windows 10?JLloydCommunity AnswerThere are a couple of ways you can turn off Windows Defender in Windows 10, both of which are discussed in the How.com.vn article "How to Turn Off Windows Defender in Windows 10". You can use the Windows Defender menu to turn off Windows Defender temporarily, or you can turn it off indefinitely by using a Registry Editor modification.
- QuestionHow do I turn on Windows Defender with Norton installed?Community AnswerYou can only have one or the other enabled. Norton Security will try to turn off Windows Defender, as it interferes with Norton's scanning feature.
- QuestionMy PC won't allow me to turn on Windows Defender, it says "This program is blocked by group policy." What do I do?Community AnswerIf you are using a work or school PC, they usually have other antivirus programs enabled and Windows Defender has been blocked centrally. You can ask your system administrator, but they will probably not do anything about it unless this is an accident (which is quite rare).
Tips
- Microsoft Defender is the best antivirus for Windows computers, so you shouldn't need to install a third-party antivirus program. All that installing another antivirus does is change the provider of the malware definitions.Thanks
References
- ↑ https://support.microsoft.com/en-us/windows/turn-microsoft-defender-firewall-on-or-off-ec0844f7-aebd-0583-67fe-601ecf5d774f#ID0EFD=Windows_11
- ↑ https://learn.microsoft.com/en-us/mem/intune/user-help/turn-on-defender-windows
- ↑ https://support.microsoft.com/en-us/windows/automatically-diagnose-and-fix-problems-with-windows-firewall-513e9cf8-19ae-d579-2092-d5e64fe06f5f
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