Create a trial version

[jimday1982]

Hi-

Does anyone know of an easy way to limit the amount of time that a user can use my program? Im looking for the simplest way to create a trial copy. Any ideas are greatly appreciated. Thanks!

 

[Divil]

Have you considered creating a feature limited version instead of time limited? If you do, you can use Conditional Compilation to make such a process quite easy.

The trouble with time-limited versions is that there are any number of ways to circumvent the protection. If the feature isnt compiled in there in the first place, theres no way around it.

 

[jimday1982]

Easy enough, I guess thats what Ill do. Thanks for the idea.

 

[Rdstne]

I have been using registry entries when I create trial versions. I limit the trial version to number of times it can be exectuted before expiring. For example, I set up an entry in local machine under software (my program), create a key, call it what ever you like, (you may be able to trick people who check for the key by naming it somthing that they would not think of checking such as: background, or font size.) If you make a 15 execution trial version set the value to 15. When you start the program use the onload to read the value of the key. Display a message such as you have 15 trys to use this evaluation, after displaying change the registry key to reflect the use of 15 - 1
Then you set the onload to determine if the key = 0 then display the message box that the evaluation has expired and end the program

You could easily set this as a date registry key. Plus you could also encrypt the info that is displayed in the registry keys.

Thats the way I would do it anyway...

 

[bri189a]

as divil said, time trial versions are easy to circumvent. Trust me, not that Ive ever done it, especially those like Rdstne mentioned. The harder time-trial ones to mess with are the ones that use an encrypted reg key in conjunction with a hidden file, or files. Users are quick to look in the registry for changes but leary of messing with a coded file (of junk) that at 974 and the 1078 byte have the value that equal the number of days its been used. The key is to make that file look like its used for something so they dont mess with it. A determined user will still figure out and as divil said the best option sometimes is just not to have the options there to begin with, but sometimes that isnt a realistic option when your trying to sell a product. Good Luck.

 

[Jay1b]

If you ask me, there is nothing more underhanded and annoying then someone filling your computer with junk.

Personally i dont want a registry full of crap, that some program left there 6 months ago, to stop me reinstalling it - especially when the program was crap and unused to begin with.

This is one thing that really should be against the law.