[Deepak]

Hi. I had build 10565 installed on my laptop which was not activated becuase instead of skipping the Product Key section, I had entered my Windows 8.1's product key in the field during installation. But my preview build was not activated. Today I clean installed Windows 8.1 and activated it using my old key.

So, my question is, to get the RTM build activated, should I use the Get Windows 10 app to reserve a copy then upgrade or can I just use its ISO file to upgrade? I don't feel like waiting for the reserved copy. I am thinking of upgrading directly using the ISO image. Will my copy of Windows 10 remain activated if I do that?

[_Emi_]

Yes, you can use the ISO, just run it on Windows 8.1 and it will do the upgrade there, click next next next and end, it will be upgraded in couple of minutes.

[Deepak]

Yes, you can use the ISO, just run it on Windows 8.1 and it will do the upgrade there, click next next next and end, it will be upgraded in couple of minutes.

It's not just about upgrading through ISO, I know it can be done that way, but about activation. I do not wish to revert back to Windows 8.1 if anything goes wrong.

[PepperdotNet]

Yes, running upgrade in any form (ISO, downloaded ESD, etc) from activated Win7SP1 or newer will result in activated Windows 10.

[_Emi_]

It's not just about upgrading through ISO, I know it can be done that way, but about activation. I do not wish to revert back to Windows 8.1 if anything goes wrong.

that's what I am saying, why would you be able to upgrade and not activate? The win7 and 8.1 key carries just like WU, and detects if you have a valid windows license to activate windows 10. and just like other upgrades from WU or ISO, you will have 1 month to revert back if you want.
Also as I remember, by using ISO you would be able to choose "what to keep" about personal files and apps, or just personal files or nothing and do like a clean install. but the key always carry like any upgrade.

[Deepak]

that's what I am saying, why would you be able to upgrade and not activate? The win7 and 8.1 key carries just like WU, and detects if you have a valid windows license to activate windows 10. and just like other upgrades from WU or ISO, you will have 1 month to revert back if you want.
Also as I remember, by using ISO you would be able to choose "what to keep" about personal files and apps, or just personal files or nothing and do like a clean install. but the key always carry like any upgrade.

Thanks.

[Deepak]

I have upgraded and it's activated. So, now can I format my local disk and install Windows 10 afresh and still don't lose activation?

[Richard Culverhouse]

@deepak: Yes. If you sign in with your Microsoft account, you don't need to enter the key and it will activate, if not you will need to get the key before you reinstall.