Danielle, a help desk technician, receives a call from a client. In a panic, he explains that he was using the Internet to research a new product when his computer emitted an alarm accompanied by a warning that a site had blocked his computer and that information was being stolen from the computer. The message included a phone number and a note to call the number within five minutes so that engineers could walk him through the removal process. ​ What has happened to the customer computer?