Got a question.

I have a spreadsheet that I'm thinking of starting to sell online (or send a CD to those who purchase it)....

Here's the key -

How do I get it to be protected from being copied....

Is there a way to make the file so that people MUST run it from the CD and can't load it onto their hard drive - or a way to get it so that it cannot be recopied?

Generally the file is in Excel - has some macros and such - but could be converted to a open source solution too....