I have hp omni 10 tablet which came with windows 8.1. I want to clean install windows 10 and want it activated with windows 8.1 license.

I followed this article http://www.howtogeek.com/224342/how-to-clean-install-windows-10/

According to that article i have to first use Microsoft upgrade offer which i did and make sure my windows 10 is activated and it will store my hardware information for activation next time. Then i have to make sure my system is uefi mode and clean install windows without key.. then Microsoft will automatically activate my windows 10 with hardware.

I followed all the steps but my windows is not activated. It doesn't activate on activating and when i force to activate it with slmgr.vbs /ato it says product key has been blocked

I have not inserted any product key and the product key that is installed it is not my windows 8.1 product key.

  • I will never understand why the the process of upgrading to Windows 10 is made to be so complicated. If you choose to keep "nothing" when you upgrade to Windows 10 the result is a "clean install" of Windows 10. Furthermore provided you current have a working installation you can "Reset" your installation and choose to keep "nothing" and you will also do exactly what happens when you perform a "clean install". You made your life difficult doing it the way you did.
    – Ramhound
    Oct 6, 2015 at 23:02
  • 2
    Back at the start of August when the license servers were often overloaded, activation issues would sometimes solve themselves by waiting a day. The messages I got back then were invalid key, and blocked key. If it doesn't resolve itself within 24 hours, the suggestion by @Insane is the way to go.
    – Peter
    Oct 6, 2015 at 23:26
  • Try calling Microsoft and explain it to them if you must. I did that and it worked wonderfully. Basically, the activation may not go through because of some patch on Windows' auth servers or a registry key somewhere. What @Ramhound said was what I recommend when doing a fresh install. Sorry if that's not helpful, but calling them is the easiest way to solve it... that or reinstall 8.1 over again and the do a 'keep nothing' upgrade. I've just noticed Insane's post below... just do that ._. Oct 7, 2015 at 2:47

1 Answer 1


You have to contact Microsoft.

I know because the same thing happened to me. If you provide them with your previous product key they can generate you a new one.

Best phone number to call is the one when you attempt phone activation, however since you're already connected to the internet I don't know if you can bring that option back up

Simply explain your situation and you'll most likely be transferred to an escalated department. Make sure you get the agents name and a case number.

  • 2
    You can still click the 'verify by phone' option when connected to the internet. Oct 7, 2015 at 2:50

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