Each software maker can hide them or may discard them after activation of their software.
-> Did you try the following titles?
MAGIC JELLYBEAN KEY FINDER
BELARC ADVISOR
Bob
I thought that Windows XP (I think it is XP Pro, SP3) had one folder that stored all of your software product key/registration/license numbers? If so, which folder is it and where is it located? Thanks for any help!

Chowhound
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GameFAQs
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