Product Key Finder won't win any creative name contests but that's not important - it's a very good key finder program.
I like Product Key Finder because it's designed very well, instantly finds product keys, allows an easy XML or CSV backup of keys found, and also lets you change your Windows registration or product key right from the tool.
Finds Keys for Operating Systems: Microsoft Windows 7, Windows Vista, Windows Server 2008 & 2003, Windows XP, and Windows 2000.
Finds Keys for Other Software: Most Microsoft Office and other Microsoft programs, and many non-Microsoft applications.
12. MSKeyViewer Plus
MSKeyViewer Plus is another good product key finder program.
Major advantages include a really small size, no install needed, and super easy interface. MSKeyViewer Plus instantly displays product keys - no scanning of your registry required.
Finds Keys for Operating Systems: Microsoft Windows 7, Windows Vista, Windows XP, Windows 2000, Windows ME, Windows 95/98, and Windows Server 2008 & 2003. 64-bit versions are also supported.
Finds Keys for Other Software: Most Microsoft Office versions including Office 2007, plus a long list of other Microsoft and non-Microsoft programs.
I'd probably pick several other key finders before MSKeyViewer Plus, but if you're having trouble finding a specific key, give MSKeyViewer a try.
geProductKeys Finder might be the most simple key finder program I've ever seen. If all you're after is a quick product key display in Windows XP, geProductKeys does the job.
Advantages include a super small download, no installation needed, and as I mentioned above, a very simple interface.
Finds Keys for Operating Systems: Microsoft Windows XP (officially) and possibly some older ones. geProductKeys does not work with Windows 7 or Windows Vista.
Finds Keys for Other Software: Some Microsoft Office programs and a few third party programs as well.
Note: You may have to disable Data Execution Prevention to use this program in Windows XP SP2 and later.
Product Key Informer is another free product key finder program but it only finds product keys for a few Microsoft programs other than the operating system.
Finds Keys for Operating Systems: Microsoft Windows 7, Windows Vista, Windows XP, Windows 2000, Windows ME, and Windows 98.
Finds Keys for Other Software: Microsoft Office 2007, Office 2003, and Office XP.
I didn't care much for Product Key Informer. I think it was the baked-in fields for specific product keys that bothered me. It's a waste of screen real estate and confirms that the program's product key finding abilities are very limited.
Important Product Key Finder Information (Windows Product Keys)
If your system was purchased with Microsoft Windows pre-installed and you have not reinstalled it or upgraded it yourself, a key finder may only find the generic product key that your PC manufacturer used to install Windows.
If you can't locate your product key sticker you'll need to request a new Windows product key.