Microsoft's popular Security Essentials anti-virus software has failed to gain the latest certificate from the AV-TEST institute. In antimalware testing against a range of products, AV-TEST failed to certify AhnLab V3 Internet Security 8.0, Microsoft Security Essentials 4.1, and PC Tools Internet Security 2012 out of a total of 25 different vendors. Microsoft's own anti-virus software failed to adequately protect against 0-day malware attacks, scoring an average of 71 percent vs. the industry average of 92 percent.
http://www.theverge.com/2013/1/17/38...28WinRumors%29
Such a huge difference in score makes me worry about people who still put their faith in MS Sec, so many better solutions out there for free as well as paid.