Term: scareware

Scareware is a form of malware designed to scare you into taking some action that further damages or infects your computer or costs you money.

Most common forms of scareware display a list of infections supposedly on your computer, and inform you that you need to purchase the “full version” to remove them. In fact, the infections are completely fake and are listed only to intimidate you into handing over money. Whether or not the software you purchase actually does anything at all is debatable, but it’s not uncommon for this program to contain even more malware.