Help with PC cleaning scam / ransomware

My grandparents are not very tech savy, and yesterday they got attacked by a "your PC is infected! Pay us to fix your computer!" Type scam. They paid $250 to OZEMIONIC and their computer is unusable. Im going over to their place tomorrow to see what I can do. They are running Windows 10. I dont know much more. Is there anything I should do or know before I troubleshoot?

Submitted June 30, 2017 at 12:19PM by BitOfAZeldaFan http://ift.tt/2snPw4D