 Microsoft Security Essentials does not run on Windows 8 and later , which has its own security subsystem . On 13 September 2011 , at Buildconference in Anaheim , California , Microsoft unveiled the developer preview of Windows 8 , which had a security component capable of preventing an infected USB flash memory from compromising the system during the boot process . On 15 September , Windows 8 developer 's blog confirmed that Windows Defender in Windows 8 would take over the role of virus protection . In an included video , Jason Garms of Microsoft showed how Windows Defender is registered with Action Center as an AV and spyware protection tool , and how it blocks drive @-@ by malware . On 3 March 2012 , Softpedia reviewed the consumer preview of Windows 8 and noted the similarity in appearance of Windows Defender and Microsoft Security Essentials 4 @.@ 0 Beta . According to Softpedia , Windows 8 Setup requires Microsoft Security Essentials to be uninstalled before upgrading Windows 7 . 
