Microsoft Security Essentials was the only entry to fail AV-Test's certification between September and October -- an embarrasing slip for the once well-regarded virus protection solution. MSSE received a total of 10.5 out of 18 possible points, most notably falling short in zero-day malware attacks. As a point of reference, 11 points are required to receive certification. The fallen AV only received 1.5 out of 6.0 for system protection, but fared better when it came to repairing infections and usability: 3.5 and 5.5 out of 6.0, respectively.