>Well, I guess I can't help you there, Satya. I've not used the Registry, or ASP or IIS. My method is a holdover from the old FPW 2.6 days and I'm simply using .MEM files on the local workstation.
>
>-Bonnie
>
>>Dear Friends
>>
>>This sounds very good. I stored the Demo Installation date in 2 places in Registry in encoded form. What I am facing problem is with the internationalization. Say if I install the Package on Norway machine then I am facing the problem in retrieving the Date. Also I do not have permission on Registry as my demo uses ASP over IIS, if I install the demo on IIS Server. Is there any way other than this method that can be used for trial checking.
>>
>>
>>>Hi Craig,
>>>
>>>I checked out your KB article because I was curious as to how other people implement this. I generally use the date scheme myself (give them 30 days, and also give them a way to extend it if they call me --- I give them a 15-digit code over the phone to enter to either extend the demo period or remove it once they've paid me). The only objection you seemed to have was that there was no way to prevent them from changing the system date. You're right about that, but what I do is save the current date each time the program is run. When you do your security checks when the program first starts, you can check if the system date is
less than this saved date. If so, you know someone screwed around with the system date and then I immediately expire their demo. Once it's expired, they have to call me to get it back.
>>>
>>>-Bonnie
>>>
>>>>>This is a general Query......
>>>>>
>>>>>I am creating a Product etc. and I want to have a Full Version and Trial Version Softwares. What are the Industry Standard Practices followed ? Are there any other methods ?
>>>>>
>>>>>Thanks in advance
>>>>>
>>>>>Satya
>>>>
>>>>Look at the KB article on my web site.
Here's how we do it
We have a DBF which is used to store certain program configurations.One of the records holds a flag and another holds the date when the demo will become unusable. This is stored in plain sight. The last field holds a checksum for the entire table and for all the fields. Editing this table then requires a special program which is NOT supplied. The calculation of the checksum program is part of youe main program startup. If the value calculated on startup from reading the table does not agree with the stored value, then Smart user has "fiddled" with the table, maybe trying to reset demo flag, or expiry date?
So we popup a screen and exit!
Of course your code MUST be protected with REFOX or some other application or the source can be decompiled and the checksum routine exposed.
Bernard
