Even if this were completely innocent request, you haven't provided anywhere near enough information for us to be able to help. Creating a key generator through reverse engineering hardly sounds completely innocent though. It sounds extremely nefarious. If you would like help on that here, I think that you're going to need to provide convincing evidence that you're not trying to crack someone else's software. Unless you can do that, this thread will be closed. If this really is your friend's application, they should be able to provide you with the information you need.