YES, Windows 7 RTM and Windows 8 Are eligible for free upgrade offer - Windows 10 Forums
I agree, but this doesn't help at the bottom of the link below.
Windows 10 Specifications - Microsoft
3 Must be running the latest version of Windows 7 (Service Pack 1) to receive the free upgrade to Windows 10 via Windows Update.
4 Must be running the latest version of Windows 8 (Windows 8.1 Update) to receive the free upgrade to Windows 10 via Windows Update.
Believe what you wish , go ahead and try the upgrade without the SP1 , guaranteed if you do it through windows update it's going to download SP1 PRIOR to the upgrade....and having windows update enabled is a requirement all across the board.. its unavoidable. This very well could be why so may upgrades have been failing and this forum has seen so much traffic as of late.
To correct the MISINFORMATION that upgrading to Windows 10 physically invalidates the Windows 8 or Windows 7 keys. There is no magic switch between the keys. All keys remain valid and useable - even together - but certain combinations may not be legal.
I have a three PC license edition of Windows 7 Premium. It only has one key. I can upgrade one of the PCs with that Windows 7 to Windows 10 and the other 2 PCs remain on the same Windows 7 key. Or I can upgrade 2 of the PCs that had that Windows 7 key and leave a third one on Windows 7 with the same key. And I don't even have to install SP1 on any of the Windows 7 PCs to do it either.
Yes, I have Windows 7 with SP1
What I want to know is should I want to start over with a clean install, can I do it?
I was able to download windows 10 from the Tech Preview site...not the Tech Preview...but Windows 10 ISO
How will I be able to do a clean install without having a key?
One last time !
Windows 10 - Upgrade Installation - Windows 10 Forums
AFTER you do a upgrade, you can then do a clean install. When it asks you for a key during the clean install, you just click the tiny little text that says "Skip", "Skip this step", or "Do this later" (or something like that). I had to skip entering the license key three times total on my clean install.
It appears you would have to perform an upgrade prior to a clean installation, due to the fact that windows 10 checks your system then generates a hardware ID hash it then sends to the MS authentication servers, which in turn give the machine a hardware based certificate allowing the free upgrade . Thus tying that upgrade to that machines hardware ID. After performing the upgrade you can then perform a clean installation of Windows 10.
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