Berj,
Read the recent posts in this group on the same subject.
If your process is really that special, Excel is the wrong basis.
You can can make it difficult, but expect that it may be broken.

If you cannot accept that, you need some compiled solution.

NickHk

"Berj" ...
Dear Anyone,

I have prepared a few excel files linked together and am planning to sell
it
to a company. But they may copy and give these files to other companies to
use on their computer. I want to protect my work. Giving passwords to open
the files is not a solution because the first company to whom I sold the
files may also give the password with the copy it makes.
So, I thought the only way to differentiate one computer from the other is
the Hard Disk serial number. If I could only link the opening of the files
(or the whole folder in which they are) to the Hard Disk serial number,
the
problem would be solved!
In this way, a copied file or the whole folder) will not work on the other
computer, unless, I intervene and link the files to the new Hard Disk
serial
number.

Any Ideas of how to do this?
Or any other way is welcome.

Thanks whoever answers.
Berj Boshnakian