I just saw this in Windows Newsletter, may be helpful:
Security Alert: Beware the Fake AntivirusSystem2011 ApplicationBe careful not to install an application called AntivirusSystem2011 on your PC. Despite its name, it isn’t actually designed to remove malicious software from your system. It is actually a piece of malicious software itself that pretends to find virus infections on your PC, and then asks you to pay a fee to unlock the full version of the program. Since there are no viruses there in the first place, this is completely unnecessary, and designed to steal money from unwary users.
If you find that you have this fake program installed on your system you can disable it by deleting its registry key. Before removing the infection, backup your registry following the steps in article R 17 of your main Windows Advisor manual, or here:
https://www.windowsadvisor.co.uk/reg_backup.html 1. Press [Windows Key] + [R], type REGEDIT and click OK.
2. Delete the registry key: HKEY_LOCAL_MACHINE\ SOFTWARE\ Microsoft\ MediaPlayer\ Setup\ Files
3. Exit the Registry Editor.