How to download Windows Defender?

Click Start and then click All Programs. 2. Look for Windows Defender in the list presented. If your computer is running Windows XP and you don’t see Windows Defender on the list, you can download the program for no charge.
For More Information Please Refer:
https://www.microsoft.com/security/blog/2007/09/11/how-to-tell-if-windows-defender-is-installed-on-your-computer/
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