I downloaded cyberdefender from a freeware site (yea- I know, you get what you pay for).I ran it and it found LOTS of problems that Windows LiveCare didn't.
HOWEVER, this freeware only identifies "problems". You have to register and pay to remove these mysterious problems. Here's where it gets fun. If you decline to pay, it becomes a "virus warning" popup.
I tried to uninstall but it didn't work. But boy that popup sure was working! Itried to remove it in control panel add/remove programs and THAT wouldn't work. Finally I went into program files and removed all files and folders that it would let me remove.
I was able to disable the program so that it's not *** me off every 30 seconds, but it took an hour of diligent folder searching, etc. to get rid of it.
It seems to me that CyberDefender antivirus is just plain vindictive when you decline to buy the software.
Review about: Cyberdefender Antivirus Free.