How to understand that a given propgram found in your computer is illegal

Question

If someone use my computer and put there downloaded programs illegally (may be a rated) software or pirated software in my PC and I want to detect all illegal programs and remove. How can I go about to find?

Answer 1

it's not possible. the only way to be sure is to format the drive.  

Answer 2

You can not tell. It is still your legal responsibility to ensure there are no illegal programs on it. This means that if somebody else loads illegal software on your machine and it is traced to you, you are the person the authorities come after. NEVER let anyone else load software. If in doubt you are supposed to remove ALL software which you are unsure of  legally. Be cautious, there is much software on the machine which is critical.  

Answer 3

if you didnt buy the software and the software is not a freeware than is most likely pirated unless the guy who installed it is so generous he paid for all your softwares which i doubt unless he's family.

Answer 4

Comtrol Panel>Add Remove Programs

Or in Vista, Comtrol Panel>Programs and Settings