Re-installed Windows 11, can't find my Product Key

Sandy Kennedy 20 Reputation points
2026-10-03T05:14:21.11+00:00

I have used a copy of Windows 11 with Parallels on my Mac for many years. I tried to put Windows and data on an external drive but Windows crashed on doing so. My fault. I've tried a download from MS but I can't activate W11 as I have lost my Product Key. From memory I purchased W11 on Microsoft online, as an upgrade from W8.1. I may be registered as any one of 3 email addresses I use. I am happy to advise those email addresses within an direct email if required. Is there a work around this issue as I would prefer not to have to buy another copy

Windows for home | Windows 11 | Licensing and activation
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DaveM121 936.6K Reputation points Independent Advisor
2026-10-03T05:51:39.57+00:00

1

If your Windows 11 licence is based on a free upgrade form a retail Windows 8.1 licence, you will not be able to reactivate Windows 11 because Microsoft changed the rules a while ago, the free upgrade licence can no longer be used to reactivate Windows 11.

2

If you purchased a Windows 11 full retail licence directly form Microsoft, log into each of your Microsoft accounts and check if you can find that purchase.

If so, log into Windows with that Microsoft account, then on the Activation settings window, click the Troubleshoot button and select 'I changed my hardware' and try using that process to reactivate Windows.

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  1. Sandy Kennedy 20 Reputation points
    2026-10-03T07:21:20.04+00:00

    Many thanks, I think you've hit the nail on the head.

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