Trial Version.

The question has been asked here a lot. Fundamentally, if a trial version includes all the code necessary to run the real application, it's likely to get 'cracked' in fairly short order unless the protection is designed by someone with considerable expertise; even then, if the application is desirable, someone will likely break it.

Generally, what you need to do for a 'good' trial version is to identify pieces of code which can be left out without preventing people from using the software for trial purposes. For something like a bridge game, you could leave out the code that shuffles the cards and replace it with some code that selects one of a hundred randomly-pre-set deals. You could also omit from the AI any code which handles situations that don't come up within those hundred deals. Until someone uses the game a hundred times, the behavior will be indistinguishable from random deals. Once the person had seen all the hands, though, the game would be rather boring. Someone who illegitimately patched the code to add a random shuffle routine could make things sort-of work, but the AI would be unable to handle many situations which would occur with real random deals.

Determining a good way to restrict the trial version may be difficult. Ideally, the program should be somewhat useful even as a trial version, but not so useful that people who could afford the real version will find the trial version adequate. Time and usage-count restrictions seem common, but IMHO they're too easily circumvented.

There's no such thing as effective copy protection. Instead of spending time making sure nobody can effectively use your software, put that time into making your application better/more reliable.

Thanks everyone and really appreciated ur help....

Application Trial Maker[^] is really helping me out..