Windows 10 install - key never asked for.

Yes, that is what I thought. In OEM computers (not custom-built) the Windows key is stored in the BIOS or firmware. So Windows 10 detected that and qualified the upgrade. That's why it activated automatically without any issue. In a custom-built PC you would have to reinstall previous Windows version, activate it and upgrade to 10.

I think an alternative is to clean install and then activate by phone. After telling some details to Microsoft representative about your previous Windows license and hardware, and based on the numbers on screen, he can determine if you have a genuine previous Windows version and give you the activation codes. He will probably ask for the previous key to examine it or the previous Windows product code (found on the label).

spapakons said:

Yes, that is what I thought. In OEM computers (not custom-built) the Windows key is stored in the BIOS or firmware. So Windows 10 detected that and qualified the upgrade.

Only on the OP's computers. Windows 10 has not detected Windows 8 keys in BIOS and qualified the upgrade for anyone else because Microsoft never wrote that capability into Windows 10. And that is why Microsoft has stated on several of their websites that an upgrade must be performed from an activated Windows 7/8/8.1 first before a clean install is done.

But if the OP thinks they had the "Windows 10 virgin birth", more power to him. Everyone else doing a clean install first has come back with "well, dang, why didn't that work?" Answer: because Microsoft didn't write it that way and told you to do an in place upgrade first.

You forget that an OEM PC doesn't need activation. The license is pre-activated by the manufacturer. When Windows is first online it simply confirms that it is installed on the intended hardware and you see it is activated in System Properties. In a retail Windows version when first online it activates automatically only when the technician has left the relevant checkbox ticked. If he didn't, the user has to click on Activate now to proceed.

spapakons said:

You forget that an OEM PC doesn't need activation. The license is pre-activated by the manufacturer. When Windows is first online it simply confirms that it is installed on the intended hardware and you see it is activated in System Properties. In a retail Windows version when first online it activates automatically only when the technician has left the relevant checkbox ticked. If he didn't, the user has to click on Activate now to proceed.

And that has nothing to do with the ability of Windows 10 to use Windows 8 Product Keys stored in bios or manually entered as a means to activate an upgrade. Windows 10 uses the license information of the previous operating system stored on the hard drive retrieved via the getosstate.exe program and resulting genuineticket.xml file as the means to activate an upgrade - not the actual previous OS product key itself.

Take a computer with Windows 8 or 8.1 OEM installed and activated by the factory, with the product key stored in bios that has never had Windows 10 installed on it. Put in a standard, unmodified Windows 10 USB or DVD created with the Microsoft Media Creation Tool, boot the computer from it, erase all the partitions on the hard drive, clean install Windows 10 to the empty hard drive. First, Windows 10 setup will ask you for a product key. Second, skip entering the product key or attempt to enter a Windows 8/8.1 product key and Windows 10 will not activate. Microsoft never wrote into Windows 10 the ability to use a Windows 7, 8 or 8.1 product key to activate as an upgrade.

It never makes use of previous OS key, but only checks for OEM activation, and if it finds it, it produces its own OEM license for Windows 10 and activates the OS with it.

Mark91 said:

It never makes use of previous OS key, but only checks for OEM activation, and if it founds it, it produces its own OEM license for Windows 10 and activates the OS with it.

Yep, that is correct. And the OEM activation is not stored in BIOS or on the motherboard anywhere - it's within the file structure of the installed OS.

Maybe I wasn't clear. During setup Windows 10 examines the BIOS and firmware for OEM previous Windows keys. If it finds them, then it determines if Windows 10 Home or Windows 10 Pro is the correct version for free upgrade and issues the appropriate license. At this point, I guess, the installation continues without giving the user the choice of version and without asking for a product key. After installation, when first online it activates automatically and that's it. If it isn't an OEM computer or Windows setup cannot find license information on BIOS/firmware it asks for the product key. At this point the user may skip it and select Home or Pro, but he will not be able to legally activate windows if he choses the wrong version. When first online, Windows will try to activate. If there is no key, it will prompt user to give one. At this point he cannot because he hasn't any, so he may be given the option to activate by phone. All of these are just guessing, I haven't actually done it, so I cannot tell. This was the case with earlier Windows versions.

spapakons said:

Maybe I wasn't clear. During setup Windows 10 examines the BIOS and firmware for OEM previous Windows keys. If it finds them, then it determines if Windows 10 Home or Windows 10 Pro is the correct version for free upgrade and issues the appropriate license.

No you were clear - just mistaken.

spapakons said:

At this point he cannot because he hasn't any, so he may be given the option to activate by phone. All of these are just guessing, I haven't actually done it, so I cannot tell. This was the case with earlier Windows versions.

That's not the way, at all, that Windows 10 does it. And this is one reason why so many people have tried to do an upgrade by starting with a clean install and thinking they can use a Windows 7/8/8.1 product key to activate Windows 10 with to end up in bitter disappointment when they find that they can't.

I never said you type your Windows 7 or 8.1 key when asked for a key, but you can tell the Microsoft representative if he asks you for that when activating by phone. Obviously he will ask you for some proof that you have a genuine previous Windows key and that you quality for a free respective (from Home to Home or Pro to Pro) Windows 10 key, before giving you the activation code. This procedure is done automatically for OEM computers as the key is stored in BIOS and can be checked by Windows Setup for validity. So if one has a genuine key of a previous Windows version he qualifies for install Windows 10 free at his computer either by upgrade or clean install. That's what I mean. Of course he cannot just type this key when asked for a key during setup! If he does a clean install he will simply skip entering a key and then activate by phone. During Windows activation by phone the Microsoft representative will tell him to type a key. That's the way it was done in Vista, 7 and 8, I have activated by phone many systems, I'm a technician.

What you were mistaken about, spapakons, is Windows 10 checking anywhere, including the bios / motherboard, for previous operating system Product Keys. It doesn't do that. At all. At any stage of installing or upgrading. It does probably check for a Windows 10 Product Key stored in bios - but if it doesn't find a Windows 10 Product Key, it completely ignores any and all other Product Keys.

It has been explained many times what Windows 10 does check for.