[AccessD] Techniques for creating Evaluation Version of Applications

Thanks Rocky.  This is exactly what I was looking for -- just wanting to
make sure that I was thinking along the same lines.  I appreciate your
input.

Stephen

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Date: Mon, 28 Aug 2006 22:28:35 -0700
From: Rocky Smolin - Beach Access Software <bchacc at san.rr.com>

Stephen:

It's pretty simple, really.  I have a 16 character key which is stored
in a front end table.  It's kind of encrypted but since it's not
viewable I guess it really doesn't need to be (like I break the
expiration date into the month part, day part, and year part, and
convert them into three different alphabetic characters and stash them
in non sequential characters in the key).  When the app starts, I
decrypt the key and extract, among other things, the expiration date.
So I just check that date against the clock/calendar and display
'License expired' and then Application.Quit. 

Since I also store the customer's name, when the app starts one of the
text boxes on the opening form has 'Licensed To: " & Customer Name &
"License Expires: " & Expiration Date.

To stop them from cheating by turning back the date in the computer,
every time the app starts I also save the current date in a table.  If
the current date is less than the last time the app was started I don't
allow it to start. Really elementary stuff, but it works.

As the expiration date of the app draws near, I display a pop-up which
says 'your license will expire in xx days.  Call Beach Access Software
for a key to extend the license'.  I have a customer tracking app which
creates these keys based on the desired expiration date.  So, I can call
up their record in my customer tracking app, generate a new key based on
whatever expiration date I want, then then email them the new key which
they enter in the pop up, and extend the license. 

The key is kind of like a Microsoft key - 6 groups of four alphanumeric
characters.

Oh, yeah, the app is compiled into an mde and the database window is
hidden, and the bypass key disabled and all that standard stuff.  I
don't use drop down menus, either, so I turn off the menu bar. 

HTH,

Rocky Smolin
Beach Access Software
858-259-4334
www.e-z-mrp.com

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Stephen Negus wrote:
Hi All,
  
I was just wondering if anyone has any techniques that they use for
creating evaluation versions of an Access application which "stops
working" after a specified period of time (say 30 days) until it is
registered (paid for).
  
Thanks,
  
Stephen