Hi Gloria. I was about to post in the other thread. You do not need to open a new one just hit reply a follow the thread. Since you are here. this is my answer: You appeared to be infected with FBI MoneyPak Ransomware, and like Ky331 said your AV is not going to get rid of it. You can follow this tutorial: [URL] Better yet if you open a topic in Bleepingcomputer: [URL] Or in: [URL] to seek expert help.
The first response did not correct the situation.   After I log on with my password, the desktop appears briefly and then I get a message from supposedly the Federal Bureau of Investigation requesting $ to unlock the computer.   It doesn't allow me to do anything.  I've taped on F8 with no results. I would appreciate further assistance.   Thanking you in advance for your help.  
Dell Laptop invaded by scam which has locked computer