Microsoft Security Essentials – is an anti-virus computer program that provides protection against different types of malware such as computer viruses, spyware, rootkits and Trojan horses. It uses the same anti-malware foundation as other Microsoft anti-virus products, although it lacks the centralized management features of some of them. This product runs on Windows XP, Windows Vista and Windows 7, but not on Windows 8, which has a built-in anti-virus component. The included license agreement allows home users and small businesses to install and use the software free of charge.
The announcement of Microsoft Security Essentials elicited mixed reactions from the anti-virus industry. Symantec, McAfee and Kaspersky Lab, three competing independent software vendors (ISVs), dismissed it as a worthy competitor and predicted its failure. AVG Technologies and Avast Software, however, appreciated it for its potential to expand the consumers’ choice of antivirus software. Meanwhile, AVG, McAfee, Sophos and Trend Micro said that the integration of Microsoft Security Essentials into Microsoft Windows would be a violation of competition law.
Despite the industry response, Microsoft Security Essentials has received generally positive reviews. Reviewers praised its user-interface, low resource usage and freeware license. Microsoft Security Essentials passed the anti-virus lab tests of AV-TEST.org and secured AV-TEST.org certification, having shown the ability to eliminate all widespread malware. According to OPSWAT Inc., on March 2012, Microsoft Security Essentials was the most popular anti-virus product in North America and the second most popular in the world. Due to its popularity, several rogue anti-virus programs that try to impersonate it have appeared.