Microsoft Security Essentials is the only free antivirus solution for your business
Even though you can find a lot of free antivirus solutions over the web, most of them cannot be used by companies. Avira’s, AVG’s or BitDefender’s free editions can only be used by users who do not profit from their computer. Basically, that’s the difference between personal and commercial use.
In this matter, Microsoft said that a company user is still an user who bought a Microsoft Windows license and therefore he should be able to use the operating system at its full potential. So, if you have a small business running with a maximum of 10 computers, Microsoft will let you use Microsoft Security Essentials. If you have more than 10, than you should use Microsoft System Center Endpoint Protection, which is an extension of Microsoft System Center – used especially by companies with a strong server-client based network.