I am attempting to create an application which, at some point, I would like to sell. I understand that any protection scheme can be bypassed. Could you recommend any ideas on what would be easy for the end user but also be at least slightly resistant to piracy.
I've had some ideas about:
The user creating an account when the buy the software then activating it once by them entering those details on the program and it downloading an update file which provides the paid functionality and is unique to that user.
Serial key which checks against an online database and activates part(s) of the software or downloads an update (as above).
No protection - just relying on honesty.
Using a basic serial key file which "unlocks" the program.
Also, how can I produce an "unlocking" system in VB 10. I've heard that showing / hiding forms is extremely easy to bypass.
I would recommend purchasing a third party licensing and activation library. It is very difficult to get this "just right", and will take quite a bit of development time that is typically better spent improving your product. For example, this option provides obfuscation + multiple licensing options including trials, etc, for under $200 US. If you value your time, it'd be difficult to hand-roll something for less money...
There are many options out there for .NET applications. A search for ".net licensing library" will return many companies specializing in this area.
来源：https://stackoverflow.com/questions/3989724/product-serial-key-purchase