SourceWindows 10 will be offered free of charge to those who upgrade from Windows 7 or Windows 8.1, but since a genuine product key is automatically upgraded to Windows 10 once you complete the transition, many wondered whether a clean install is possible or not.
Microsoft has confirmed today, through the voice of Gabe Aul, head of the Windows Insider program, that clean installs will be possible for those who upgrade to Windows 10 for free from any of the supported Windows versions, but no other details have been provided.
He has mentioned that you will be able to clean install Windows 10 on that PC at any given time for as many times as you want, so probably, your product key for Windows 7 and Windows 8.1 can be used for re-activating Windows 10 automatically in case that happens.
“You will not need your 8.1 key, the same device will reactivate once it has been successfully upgraded to 10,” Aul has explained.
Windows 10 will be supported on PCs and laptops eligible for the free upgrade for the entire life of the device, so once the one-year free upgrade window comes to an end, you will continue to receive updates and security patches.
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This was one of the concepts we tried to wrap our minds around back then... Windows 9 Will Support Unlimited Activations on Same Hardw - Windows 10 blog
Thus, assuming the underlying OS qualifies for the upgrade vis-a-vis specification and legality, the MSA and deviceID is linked to the activation of the upgrade and any subsequent installations on that device, using the same MSA, will not require a key.
It's good news.. I hope the source has it right this time.
great news indeed
I've added all the reliant tweets to the first post for clarity.
Oh good, that's way better than we expected.
Also stated here,
Good news indeed. I still want to know what happens when we replace/upgrade components (Motherboard and HDD in particular). Hopefully they will clarify soon.
Lack of info here is beginning to bother me as well. People have been wondering what the "gotcha" might be behind the free upgrade...if it's true that from now on that every licensed copy of Windows is tied to a specific piece of hardware...then that is exactly like OEM versions work today with Win7/8. You can clean install OEM Windows an infinite number of times right now, but the catch is that that's only true on the original motherboard...! If that what's Microsoft means, then I fear that is not going to make people happy--not at all.
Why would you expect it to work any differently?