Aashish, the usual is when the app is first run the date is stored in some hidden location and optionally encrypted. This could be in a hidden file, in a non-obvious registry key, or even in a normal table field but encrypted. Then each time the app is run you can check days expired since this first start date.
Of course one can turn the PC clock back so if you wanted you could test for this too. You could store the latest date each time the app is run and test for the computer clock being moved back and you could also add in a maximum number of times the app can be loaded for instance.
>Dear Friends
>
>I am looking forward to make a demo copy of my VFP7 based software. Wish to implement a 30 day expiry logic. Any idea.
>
>Aashish
In the End, we will remember not the words of our enemies, but the silence of our friends - Martin Luther King, Jr.