On 4 June 2014 17:40, Rich Cooper <[email protected]> wrote:
> All a user has to do is reset the clock back to installation time to > counter this, but it seems like a lot to give up compared to paying for > software full operation. There are many timed programmes out there that have this problem yet others know if you have set the date back. What I do is to record in the registry, under a meaningless key, the last date that it was used, that way if the date has been moved back the software will know. I am sure that there are more sophisticated methods but a determined hacker is hard to stop and in any case most users won't know where to start to get around such difficulties. You'll be protected in the majority of cases and if one slips through the net then it hasn't cost you anything, which is the beauty of selling downloadable software. I take the view that there are a few people out there who will try to the limit of their ability to get around any restrictions but successful or not those people are unlikely to buy the software anyway. Therefore you have lost nothing if they succeed and you never know they may even tell others about your software which widens the pool of people who get to know about it. Most people are honest and you won't have any problems, to prevent the less honest ones you have to consider the balance between the effort that it would require to prevent the one or two hacks and the loss to you if someone succeeds. PS. I just remembered another method that I have used. Most if not all users will not think to put the date back until the programme stops working. So when the programme is started for the first time after the limit date write a 'stop' entry to the registry before advising the user that he has exceeded the limit. Then whatever date is set by the user the registry entry will advise the software to not run. Regards Tony Foale [email protected] http://www.tonyfoale.com http://picasaweb.google.com/tonyfoale https://www.facebook.com/tony.foale.5 https://www.youtube.com/user/MotoChassis _______________________________________________ Delphi mailing list [email protected] http://lists.elists.org/cgi-bin/mailman/listinfo/delphi
