First, let me say that I’ve seen several compromised systems in my office, and currently working on one with a variant of cryptoware 2.0. Not a fun task telling a customer that their files have been encrypted by a criminal overseas, and that their chances of getting these files back are slim and none. So what is ransomware?
Ransomware is a type of malware which restricts access to the computer system that it infects, and demands a ransom paid to the creator(s) of the malware in order for the restriction to be removed. Some forms of ransomware encrypt files on the system’s hard drive (cryptoviral extortion, a threat originally envisioned by Adam Young and Moti Yung), while some may simply lock the system and display messages intended to coax the user into paying.
Can it be removed? Yes. The issue is that the longer you use a system that is infected, the greater the chance you will lose more and more valuable files, not to mention that your personal information can be compromised. If your system is infected, do not pay bills, do not use websites that require a log in username and password, in other words a compromised system is one that can cost you more than a trip to a local computer repairman.