I just did an inventory of my Windows keys because I am selling an old laptop with a DAW (Digital Audio Workstation) and I wanted to include the original Windows CD with it.
I realized that two of my desktop PCs that were upgraded from Win 7 Home Premium (each with its own product key) now have the same Windows 10 Product Key.
Is this a problem?
I have a feeling those are generic "installation ID keys" rather than product keys. Could be wrong though. Compare to known generic keys.
Are they the generic Windows 10 keys. You can reference this tutorial.
Generic Product Keys to Install Windows 10 Editions
Short answer, no.
If you re-install clean MS will check your device and if licensed before it will activate again.
If it's the generic W10 Home key ending in -8HVX7 then no, it's normal. All my W7 Home Premium machines got that key after upgrading to W10 Home.
A machine that got a free upgrade from W7 to W10 has a digital license stored Microsoft's activation servers and linked to the hardware ID of the PC. It is this hardware ID that entitles the PC to activate W10, not the installed generic key. You can clean install the same edition (Home in your case) and skip entering a key when asked. It will activate automatically from the existing digital license as soon as it can contact the activation servers.
NB: the HDD plays no part in the hardware ID, you can replace it or upgrade to an SSD without affecting activation.
Mine both end with 3V66T.
They have both been running for more than a year, so I guess that if Microsoft had a problem with it, I would have heard something by now.
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