Sorry, Dom. If you're looking to create a commercial program with
buttet-proof security, you're working with the wrong application. Excel's
password security is only effective in helping prevent inadvertent meddling
by anybody and intentional meddling by the technologically naive. Any
workbook's security can easily be broken by cheap off the shelf software or
(for the slightly technically oriented) easily downloadable code from the
internet.

For secure applications, you'd need to develop in one of the popular
programming languages.

***********
Regards,
Ron

XL2002, WinXP-Pro


"Dom" wrote:

I want to create a worksheet that I can sell to people. To stop them passing
it on to non-paying people, I want to find a way to generate passwords that
will be unique to each customer by using data on their PC. Does anyone have
any idea how this could be done? I would be building it in Excel 2000.
Thanks.