Expiry Date - VB App

[Brianchetty]

Anyone has code to make an application expire after 30days?

curious of how its done

Thanks for your help
Brian

[phinds]

put a date in the registry then have your app test it. You should use some obscure name for the registry entry, NOT the name of your app, thus discouraging folks from finding it. Pros will be able to find it 'cause they can snapshot the registry before installing your app and then see what changes from installing your app, thus seeing your entry, but the number of people who will do that are insignificant in the general population.

[Franky]

In other compilers exist for this expiry options, but I think not in VB. Maybe as a 3rd party add-on.
If you want to do it then is the question on how many PCs your program will be installed. I guess on more otherwise you wouldn't need the 30 days.

Ok, how to do it:

I make it in that way that I use in a Database or in a file a crypted line in which I upgrade every day. But many people turn the date back if they need to do that. So i count always for every day 12 hours, that should be enough. If a day have more then 12 hours i guess that the date is set to the day from before and i block the program. This file includes the ID from the installed computer and the date and added hours. A problem is that many people just delete this file, then you have normaly no way to control them from cheating. But there is a nasty trick, not very clean, but it works; at least with the most users:
You install in the windows/system directory a file, for example: Mshfl21.srg
This file is a placebo and is of course no systemregisterfile. But the normal user don't know this, and in this file you store the crypted data that i said before. But use the same system as they use in the normal srg-files, so if somebody view it, he will not get suspicious. And set the date of the file and the time of the file on the same date/time as the standard-srg-files. It is very difficult for a user to find this file. So you know when somebody reinstall the program that the program was already installed.

But, as I said, it is not a serious way, but the user who try to steal your program use not serious ways too.

Franky

[Brianchetty]

Thanks for the response guys,

i like Franky's way - do you have some code to share- thanks

Does anybody have some code that i can use just to get me started?

phinds - do you have code to do this?

thanks
Brian

[Beacon]

go to www.planet-source-code.com there'll be some code there for you!

[Franky]

If you recognise that somebody use a program from you without getting the permission from you then DON'T delete the data and DON'T encrypt the data from the user. Just block the program. It is in the most countries against the law to block data in any way from a user. It means that the user did not pay your program but he lost maybe a lot of business because your actions and that can be expensive. The owner of the program is NOT THE OWNER OF THE DATA!!! I just want to say it in case somebody got this idea ....

Franky