Microsoft Security Essentials

A very lean package.

*This is included in Windows 10.

It is called Windows Defender.

Malwarebytes Anti-Malware

Awesome companion in fighting malware.

You can install and use as a trial version. This is actually worth paying for. Removes all infections your computer can get.

Malwarebytes 3 reverts to a manual scanner (after 14 days) that detects and cleans up malware infections only when you run a scan. You can upgrade to Premium at any time.

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