Microsoft Security Essentials (MSE) is the company’s free anti-virus and anti-malware application, and it works really well for personal computers, and it does a good job of operating in the background without disrupting what is going on in the foreground.
The Security Essentials home website has a new link where you can download a beta version of the application. MSE has not changed much since its initial release, so a face-lift along with some functional enhancements is long overdue. http://windows.microsoft.com/en-US/windows/products/security-essentials
