You could consider looking at some of the items used by XP's
(infamous) "copy protection" scheme.
However as pointed out by many, you will then have to deal with
customers' frustration following changes to one or more of these
components.

What is the exact scenario you want to deal with, and how strictly do
you want to enforce your copy-protection scheme?
Given that it's not particularly difficult to access even
password-protected VBA code in Excel, a less "heavy-handed" approach
may be preferrable.

Tim.


"For example, XP looks at the microprocessor serial number, a 96-bit
number, and hashes it to create a 128-bit number. Six bits from this
resulting number are used in XP's hardware hash.

The 10 devices used to create the hardware hash a

1. Display adapter
2. SCSI adapter
3. IDE adapter
4. Network adapter MAC address
5. RAM amount range
6. Processor type
7. Processor serial number
8. Hard drive
9. Hard drive volume serial number
10. CD-ROM/CD-RW/DVD-ROM"

"alan" wrote in message
...

Tim, Thanks for the response. I'm able to read the
registry, but the problem (as you described) is the
organization of the registry. Where do I look in the
registry to find the Excel Product Id Key for all Excel
installations?

I have MS Office 2003 installed. To obtain the Excel key,
I use:

"Software\Microsoft\Office\11.0\Registration" &
Application.ProductCode

and the "ProductId". This gives me the Excel Product Id
Key displayed by Excel Help.

I doubt this will work if the user has a different
version of MS Office installed or only Excel. Your
example illustrates this. I need the general method to
find the Excel key.

Does anybody know how to find the Excel Product Id key in
the registry for all (most?) Excel installations? I need
the key displayed by Excel Help.

Also, Please submit any suggestions you have for better
machine specific key(s).

thanks.