Why Windows Defender Won’t Open in Windows 11
Here are some examples of situations where Microsoft’s anti-malware app won’t open or work properly:
There’s a temporary memory-related issue where the app won’t scan for malware.Windows Security opens normally, but then promptly closes a few seconds later.Another software program is “fighting” with Windows Defender, and it’s throwing error messages.You see an error that says, “You’ll need a new app to open this windowsdefender link.“You recently installed or uninstalled another virus protection program, and now Windows Defender won’t open.
How to Fix Windows 11 Defender Not Working
There are several things you can try, but follow this list in the order it’s presented to address the easier solutions first: Microsoft Defender won’t catch active malware unless you have Real-time protection turned on. Follow that link for two methods—one uses Settings, like in the image below, and the other uses a PowerShell command that’s helpful if you can’t open Windows Security at all. If that doesn’t work, you can try an offline Microsoft Defender update. Choose the latest version from that list, likely called Update for Microsoft Defender Antivirus antimalware platform. To address this, open the following folder. One easy way to do this is to paste this path into the Run dialog box (WIN+R): Select everything in the Service folder (Ctrl+A), and then press Delete to clear it out. If you find the other program is to blame, or you suspect it might be but disabling it didn’t help, use a program uninstaller tool to completely delete the software. If you still can’t start Windows Defender, there are a couple of registry keys you can delete to re-enable it. This might happen after uninstalling another antivirus program. Open this key, and delete these two registry values from there:DisableSpyware and DisableAntivirus. This is a sure fix for whatever problem is affecting Windows Defender, just make sure you wait until you’ve tried all the above before completing this drastic step.
