Windows 10: Need a product key for Microsoft order Windows 10 Pro

I purchased Windows 10 Pro online, but no product key was emailed to me. Any ideas?

:)

 

Product Key not on Order Page

I ordered an upgrade from Windows 10 Home to Pro recently. The upgrade occurred automagically, but I now have no product key. I spent some time and went to my account, finding the order and selecting it. Microsoft support under "Product Key" says to

Go to Order history, find ,
and then select Product key/Install

I looked at the order summary and detail on Order History. There was no Product Key. Much appreciate some help.

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windows 10 key

Thanks but I don't want to do any decrypting. I want to download a Win 10 ISO from Microsoft and install it using my Win 8 key. No other steps required. Is that possible?

 

Windows pro product key re-usability

This is an informative question regarding the policies of windows. I have an existing Microsoft Windows Pro software installed on one of my devices, I wanted to know if there is a way using which I can use that product key on my another device which has
Windows home installed in it, to upgrade it to Pro. If the policy requires the earlier existing system(with windows pro) to be abandoned or removed in order to allow the product key of pro to be used in a new system, that too works for me.

Please help me by suggesting me steps to take.

Thank you