[Vicky.]

OK. Sounds like this is a trojan called Reveton. Search up on that...I sorted one of these out for a friend years back so will look into it now. You obviously know this but do not send any money anywhere, the one my mate had was asking for $300 to be send by 'moneypak' to unlock the computer.

Also if you do any internet banking or anything, contact your bank to let them know to be on the lookout. There is a very large chance these scammers have remote access to your computer right now