I have an Excel Workbook I want to distribute. I want to copy protect it. I
want to be able to email/post it to users, on first use they will be
prompted to enter a code, distributed with the workbook, they will then
connect to the web, and receive an 'unlock' key.

The web side of things will need to keep count of how many licences they
have bought.

Any ideas? I thought of doing this via a small vb app, then using one of the
many 3rd party protection systems to protect the vb app, which will in turn
open the workbook (perhaps with an encrypted password?).

Security isn't massively important, this doesn't need to be to banking
standards. I just want to track who has paid for it and prevent casual
copying. It isn't a mass market product to I doubt it'll appear on Warez
sites. The data in the spreadsheet isn't important, it's the structure and
formulae etc. The data isn't sensitive.

Yours, Mike MacSween