I will second the comments made by David Biddulph - if you publish it in
Excel, I can get into it and if the incentive ($$ or just plain curiosity) is
there, I'll reverse engineer it from that point even if you've obfuscated
worksheet functions and code processes.

I went through this same discussion with a gentleman on these very boards
maybe 2 years ago. He has an excellent, useful and almost unique product
that he worked very hard on. When it came time to think about distribution
and sales, we were simply stopped by all efforts to protect it, including
possible methods such as using an Excel "compiler" to protect the package
(they were not sophisticated enough, or took away from the ability to expand
rows/columns for additional data within the package). His solution: he went
to a professional coding team and had the entire project redone in another
language so that the compiled product could be released, but without the
source code going along with it.

An NO scheme is 100% protection against unauthorized copying/distribution -
just look at all of the money that Microsoft has tossed at that effort over
the years, not to mention the efforts and jackboot tactics that organizations
like the RIAA have taken to prevent such things --- and then look at the
results: there are still illegal copies of applications, music, movies and
anything else still making the thieves big bucks.

"JBW" wrote:

I have written a very detailed carbon footprint calculator for a large
packaging company and we're just about to go through third party
accreditation.

We now want to enable other users to make use of it.

How can we do this and protect it from being copied, sent, emailed etc