Is there a software which prevents illegal distributing of my Windows application [closed]

Question

The subject itself is saying :

1. i created application for Windows 7 based on .Net 4
2. i want this application to be used only by legal users who really bought it
3. thus i probably want some software that could help me to prevent situation when some user buys my application and starts selling it under his name

Could you list existing software responsible for this or at least describe theoretically how can i achieve this - saving hard drive information to the registry or so?

Update 1: seems that comments below require more description inside this topic :

@svick no, i really think that month of my work worth of adding small troubles to pirates trying to make money on me without any efforts, i just want them to spend some efforts cracking my software - that is all, under small troubles i mean simple key / pass verification or something like that ...

Also i really believe that sharing is caring and 5 my previous applications i provided for free and now it is time to compensate some of my time

I also believe that there is no absolute defense because there was time when i also cracked some applications with disassemblers like IDA and so on, it is just a matter of time but all i want currently is just to return last month of work and some donation for those 5 applications provided for free ... i hope i was clear enough here ...

The main idea - if pirates want crack my application and redistribute then they also must work - at least on cracking, they must spent as much efforts as approximately i did :)

Answer 1

Ultimately the answer is: there is no such system.

Since the user—owner and administrator—of the computer has full control they can fake anything (with sufficient effort) up to and including any attempts by your software to call home for verification. Remember they can always modify your software (including eliminating checks against such modification) as part of this.

You are better off providing sufficient cost-benefit to the user (eg. useful functionality, responsive and useful ongoing support) that it is their interest not to cheat. This includes making it easier to be honest than dishonest (this is one of the major problems with media DRM).

While you can get arbitrarily close, with significant effort, to your goal you will of course be taking resources away from implementing things of use to the user.