Product code for Win 10 Clean reinstall after upgrade

I have downloaded the Windows 10 Pro ISO file from MS and burnt it to a DVD.

It offers to install it as an upgrade over my Win 8.1 Pro installation on my PC.

Once I have done this, can I then format the hard drive, and do a clean installation of Win 10 on the same machine without a product code?

I'm assuming the product code will be installed in the BIOS and not needed to be put in manually?

Can anyone confirm that I have correctly understood how it works?

Mustang said:

I have downloaded the Windows 10 Pro ISO file from MS and burnt it to a DVD.

It offers to install it as an upgrade over my Win 8.1 Pro installation on my PC.

Once I have done this, can I then format the hard drive, and do a clean installation of Win 10 on the same machine without a product code?

I'm assuming the product code will be installed in the BIOS and not needed to be put in manually?

Can anyone confirm that I have correctly understood how it works?

Yeah, that should work. I clean installed 10 this morning and it's still activated. I was coming from 10 IP, but it should work for 7 and 8.1 as well.

This is indeed true. When you clean install after installing it as an upgrade, you'll be able to skip the Windows 10 key prompt during clean install after which it will be activated regardless.

Read here: Installing Windows 10 using the media creation tool - Windows Help , you'll find the following written about doing a clean install and it asks you for a key:

"Note

If you upgraded to Windows 10 on this PC by taking advantage of the free upgrade offer and successfully activated Windows 10 on this PC in the past, you won't have a Windows 10 product key, and you can skip the product key page by selecting the Skip button. Your PC will activate online automatically so long as the same edition of Windows 10 was successfully activated on this PC by using the free Windows 10 upgrade offer. "

While everything said is true, Don't be surprised if you have issues activating the 2nd time, the activation servers are dead in the water and it may take a few days (I spent 45 minutes dealing Microsoft support about this exact issue)

People in this forum have reported earlier that it was taking 3+ hrs sometimes to have everything get caught up on the MS side. They say it does indeed switch over to activated.

The info on what you upgraded is saved to the UEFI firmware chip, which is then checked when you do the ISO boot & fresh install.

So there will just be MS lag for a period of time before you are switched over to activated.

MS "Soon."

The product key is not stored in the BIOS. Windows 10 doesn't touch your BIOS.

Mystere said:

The product key is not stored in the BIOS. Windows 10 doesn't touch your BIOS.

That's true as far as I know!

blackroseMD1 said:

Yeah, that should work. I clean installed 10 this morning and it's still activated. I was coming from 10 IP, but it should work for 7 and 8.1 as well.

It never asked for a key rite?

The only thing I can think about is that MS is recording all your hardware details after you did a UPGRADE. But I don't think so, and it doesn't sound to work that way!

jyusa said:

The only thing I can think about is that MS is recording all your hardware details after you did a UPGRADE. But I don't think so, and it doesn't sound to work that way!

Yes, MS is recording them.