There are many ways to open windows defender in Windows 10 devices. You can choose any one of them according to your liking or convenience. Here is the list of ways to open Windows Defender in Windows 10 based devices.
1. You can open windows defender by searching in the windows search box.
2. Or you can click the start button and select All Apps and then open windows System and tap on Windows defender.
3. You can also open it using the settings app in windows, tap on Update and Security and then click on the Windows Security option.
4. You can also access it via Run window on your system.
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