 A September 2011 OPSWAT report found that MSE had further increased its market share to become the second most popular AV product in the world , and remained the most popular in North America . OPSWAT reported in March 2012 that the product had maintained its position , and that Microsoft 's market share had improved by 2 percent worldwide and 3 percent in North America . Seth Rosenblatt of CNET News commented on how the product 's share rose from 7 @.@ 27 in 2010 to 10 @.@ 08 in 2012 , stating that " use of the lightweight security suite exploded last year " . 
