System Security System Tuner Came on the internet as a upgrade to my virus protection. It block me out until I purchase this product Internet

It is NOT part of Microsoft. You were redirected while on the Internet to a bogus site that proceeded to tell you that you had non-existent viruses on your computer. The easiest way out of the situation would have been to click on Start and Turn off your computer. On Startup your computer would have been OK.

If instead, you proceeded and clicked on their download to supposedly clear your computer of the non-existent viruses then, you were suckered into paying for something that was not necessary. 

As you are running Windows Essentials and I therefore presume Windows7, go to control panel and select Windows Defender. Let it do a scan to see if you have any malware. In control panel click on "view large" icons to find settings easier. Also read the entire article in the link provided below.

  
 
http://www.pcworld.com/businesscenter/article/224125/lizamoon_attack_what_you_need_to_know.html