Microsoft Security Essentials: Free, so what's the catch?

Personally, I didn't like Microsoft's Live OneCare security software; every time I worked with it on someone's computer, there was a problem of some sort. Windows Defender, however, as an antispyware tool has gained my trust over the years.

Source: http://www.infoworld.com/d/windows/microsoft-security-essentials-free-so-whats-the-catch-105?source=rss_windows

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