Here is a little info on Conficker. It is still around and causing problems for more and more people.
Conficker uses pop-ups to warn of PC infection and offers fake antivirus software, called ‘SpywareProtect2009’ at a price of $49.95. If purchased, credit card information is stolen and the virus downloads even more malicious software.
The bad thing about getting the pop-up ‘SpywareProtect2009’ is that it usually freezes your PC. The only way to shut it down is with the power button. (You will never see me recommend this for anything else. Its not a good idea.) If you have AVG or Norton installed they will pick the virus up and quarantine it when you reboot. There are others but I know these two work for sure.