Most AntiVirus programs are crap at picking up that type of program, typically called "Scareware" or "Fraudware". Here's what you should do. Go pick up MalwareBytes. Get the paid version because the $25 for the auto-update and scan plus 0-Day protection is gold. I managed to get my copy for less due to a Black Friday sale. And it's FOR LIFE. No yearly repurchase. You can transfer it to a new computer if you get one. And it's the most effective malware program I've ever used.