How to Reinstall Windows Defender in Windows 11
Windows Defender (aka, Microsoft Defender) isn’t installed on your computer like a typical program, so you can’t reinstall it like you can regular software. Instead, follow these directions to use a PowerShell command to get the job done. It might take anywhere from 5 seconds to a few minutes to complete. If you can open Settings normally, there’s an easier method after these steps. Another way to reset Windows Defender is through Settings. If Settings opens fine for you, you don’t need to bother with a PowerShell command. Instead, go to Settings > Apps > Installed apps > Windows Security > three dots > Advanced options > Reset. If that doesn’t work for whatever reason, use the search bar on the taskbar to search for PowerShell, and then right-click it to find the Run as administrator option.
When to Reinstall Windows Defender
Technically, you’re not really reinstalling the program because Windows doesn’t actually let you uninstall it. That said, you might run the above command to reset Windows Defender if it’s just not working correctly. The most obvious sign you need to do this is if you see an error when you try to open it. If it’s not opening as it should, and you see this message, the above command should fix it right away: Or, maybe it does open, but some of its toggles won’t turn on or off, or you can’t even find a link to it on your computer. In these cases, the PowerShell command should refresh the tool back to working order.
Windows Defender Might Just Be Off
It’s possible that you’ve considered reinstalling Windows Defender because it isn’t catching malware, when in reality, it’s just not turned on. You might think it’s been uninstalled or is broken, but really it’s just disabled. This is completely possible since Windows 11 lets you turn off its built-in antivirus program if you’d rather not use it. Learn how to turn Windows Defender on and off for specific directions.
