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ProduKey 1.35
ProduKey is a small utility that displays the ProductID and the CD-Key of MS-Office, Windows, Exchange Server, and SQL Server installed on your computer. You can view this information for your current running operating system, or for another operating system/computer - by using command-line options. This utility can be useful if you lost the product key of your Windows/Office, and you want to reinstall it on your computer.
ProduKey works on all 32-bit versions of Windows. However, some features, like viewing the product keys of another operating system instance, are only supported on Windows 2000/XP
Download: ProduKey 1.35