How can I know the Windows product key if I don't have it?, different Key finder software give different keys!!

Rodion15

Distinguished
Sep 11, 2011
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I'm re-installing Windows for a friend but he lost the Windows key and the label is so worn out it can't be read.
I've tried to get the product key using different software and was surprised to obtain different Product keys.
Everest by Lavalys and HWinfo give me a different product key than Produkey and Magic Jellybean. What's the real one?
I'd welcome any help.
 

Dee Kay

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Dec 22, 2014
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Unless there were multiple versions of windows installed then you should have the same key identified by the different ID programs. Why not try the keys reported to see if they are recognized by MS as being legit for that install?