How to control expiration date of our software in demo mode?

Posted on 2007-10-10
Last Modified: 2010-04-11
I've got encrypted Serial Numbers and Activation codes working in some new software I'm writing.  However, I'm not sure how to best handle controlling "demo" mode.  Most companies simply allow their software to run in demo mode for 30 days after installation.  I'm unsure as to the best way to compute this value.  I'm using Visual Basic 6.0.  One option is to store an encrypted date of installation in the registry.

Any other ideas?
Question by:ljpitre
    LVL 27

    Accepted Solution

    I would store an encrypted date in the registry after e.g.

    "safe file" is triggered.

    Most users will check the installation procedure with tools like regmon and filemon.

    But setting / checking that value only during certain actions grants you some obscurity. I would also just check the value with a random propability, like just in 1/3 of all file saving cases or after the application ran an hour...


    LVL 24

    Assisted Solution

    Take a look at Activelock
    LVL 1

    Expert Comment

    Forced accept.

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