Security Essential is a rogue security application that attempts to falsely detect malware on victim’s computer and prompts victim to pay for removal of those false detections. What is interesting about Security Essentials is the way they entice users to install their rogue application. Security Essential when execute will first pop up a window which looks similar to Microsoft Security Essential (this is legitimate application from Microsoft), informing the user that the computer is infected with malware.
http://blog.pctools.com/freeav/2010/news/antispy-safeguard-security-essential/