Computer Virus Help Needed

What worked for me, when I got a nasty virus (FBI I virus locked my computer and deleted all of my restore points) was a "offline" version of Windows Defender. It will eliminate the virus before your windows boots up. You will have to put it on a cd and let your computer boot from it. Make sure you download the correct version 64 bit or 32 bit.and oh, it's free by the way. Good Luck