Be weary of anyone calling you from “Windows 7” (or similar Microsoft brand names) telling you that your computer has reported a problem that they can fix…for a price.
Microsoft says that their employees do not cold call its customers. Any recieving a call like this should simply hang up.
http://www.smh.com.au/technology/security/pay-up-or-your-pcs-toast-20100630-zm8i.html