Database 30 Day Password

[Rod]

I would like to distribute a database for standalone use but have it only
work for 30 days at a time. To enable it to work for 30 days at a time I
would like to require the user to put in a password which I will provide.
This password needs to be generated on my end monthly and the users end
should be looking for this password every 30days; without this password the
database should not open. The password is to change every 30 days. How can
I do this?

Thanks MUCH!

 

[Tom van Stiphout]

On Fri, 16 Jan 2009 04:52:01 -0800, Rod

There is nothing built-in that can do this, but you can write a VBA
function. It would generate a password based on an algorithm that is
difficult to predict for your user. For example it can use a random
starter password of "dlso2cug65shlkug" and the next one is 1, 2, ... N
ascii values higher than the previous letter: "envs..." etc. Of course
you need to wrap-around after "z".
Be sure not to lock the DATA for the user; that is typically frowned
upon and may be illegal in many jurisdictions.

-Tom.
Microsoft Access MVP

 

[Rod]

Sounds like that could do it - simple. Any ideas where I can find an example
or get some help?

What do you mean by lock the DATA?

 

[Tom van Stiphout]

On Fri, 16 Jan 2009 06:47:02 -0800, Rod

The thing with these algorithms is that they should remain somewhat
secret, so you won't find much help. But it's really not that
difficult; the keywords would be Mid$, InStr, Chr, Asc.

What I meant is that you would not want to make the data inaccessible
to the user, just the application. Hijacking one's data is frowned
upon, whereas disabling one's program for non-payment is capitalism.

-Tom.
Microsoft Access MVP