Licensing

[ansuman_behera]

Hi,
I want to distribute an application developed by me but would like to allow users to download the demo version, which should expire after 30 days. The problem is how to check if the 30 day period is over ? I can check for the system date but then the user can change the system date and run my application even after the licensing period is over. Can I restrict this in any other way ???

[Chris Eastwood]

Take a look at the ActiveLock control from

http://www.insite.com.br/activelock/

It's free and will allow you to create time-limited demos (it even recognises when the user changes their date to try and fool it).

Whats more, it's free !

Chris Eastwood

CodeGuru - the website for developers
http://www.codeguru.com/vb

[ansuman_behera]

That was cool !!! But I've a doubt. This ActiveLock must be storing the information like LastRunDate, DaysUsed at some place in the system only, most probable place beign the system registry. What if the user changes them ??? How do I know that the system has generated proper locks ??? Basically, where is this information stored ???

[Chris Eastwood]

From what I can find, the information is encrypted into the registry (you could probably find it using one of the registry monitoring programs available, but whether you could un-encrypt it....) - the only problem I've found is that a user may buy your app, then need to reinstall windows for some reason. This then means that their registration code will no-longer work. You'd have to mail the developers at activelock for more specific information (they're a nice bunch of people, very helpful).



Chris Eastwood

CodeGuru - the website for developers
http://www.codeguru.com/vb

[ansuman_behera]

thanx a lot, I'm really sorry 2 ask this but i do not have the activelock guys e-mail, neither could i find anything on their website. can u just send me the e-mail id ??? Thanx again....

[Chris Eastwood]

You can ask for feedback from the team at :

http://www.insite.com.br/activelock/question.html



Chris Eastwood

CodeGuru - the website for developers
http://www.codeguru.com/vb