It is an antivirus provided by the Microsoft team for free. It comes pre-installed on every Windows 10 based device. Once you activate your windows, the antivirus gets activated too. But you may have to turn on the real-time protection on for complete all-round protection. It is a good antivirus and ranks only below Avast free antivirus.

Here is how you can enable Windows Defender Realtime protection in windows 10.

1. Open settings from the button in the start menu and click on the Update and Security option.
2. Then, you need to select the Windows Security option from the left panel.
3. Now, you click on the Virus and Threat Protection option.
4. Then, click on the Additional settings and toggle the Realtime protection Switch from the next window.

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