ProduKey is essential in
retrieving product key and you want to reinstall it. Aside from Windows and
Microsoft Office, it also generates and display the product key of Exchange
Server, and SQL Server. You can view this information for your current
operating system or another using the command options.
ProduKey also allows you to recover keys from external Windows installation that are plugged into your computer or accessible through the network, this allows you to recover the key even if you cannot start the operating system.
Get the product number of your Windows OS using this program.
Also check out the forums for Windows.