You'll probably need to do some kind of activation online, maybe with a web service - and that web service will only activate the software once. I don't think you'll ever be 100% sure that they don't install it more than once, but you can make it tricky to cheat - like dumping a unique GUID in the registry at the time of installation, then passing that on to the web service for activation and returning a cryptographically signed response, also stored in the registry - this way, the user never sees the key or has any idea what it's doing. The application would check the registry when it runs to ensure both keys are in the registry and they match.
I'd imagine there are already tools out there to do it, but if you want to write it yourself, you can do something like this. On Dec 3, 9:50 pm, Muhammad Arif <[EMAIL PROTECTED]> wrote: > what my question is how can i restrict a user to install my software > on only one system. > > regards
