Windows 10: Im am a new user to my windows 10 pro.I do not know what product key,but the laptop keeps...

I'm a new user to my windows 10 pro and I would like to activate my windows.But in order for me to do that,i need a product key which i know nothing about please help me out.

:)

 

Windows 10 Pro product key on old laptop not working on new laptop

In 2015, I upgraded my old laptop from Windows 8.1 Pro to Windows 10 Pro via the free upgrade that Microsoft provided. My old laptop had an OEM 8.1 Pro key, and thus the 10 Pro key was a genuine product key, direct from Microsoft.

Fast forward to the day this post is made; I have a newer and much more powerful laptop than my old one. I decided to take the 10 Pro product key from my old laptop and use it on my new one (the new one had an OEM Windows 10 Home key). I deactivated the 10 Pro key on my old laptop and upgraded my new laptop from 10 Home to 10 Pro. However, I cannot get that key to activate 10 Pro on my new laptop.

It is important to note that I do not have my old installation of Windows 8.1 Pro on my old laptop as I deleted it years ago to increase the space on my hard drive.

I contacted Microsoft support to help me activate the key but to no avail. When I gave them my 10 Pro product key, they said it was invalid and not genuine. They also added that I should contact my vendor for a new key. In my case, wouldn't that vendor be Microsoft themselves?

The error code I am getting is 0xC004C003.

Can someone please help me resolve this issue?

 

Windows 10 Pro product key on old laptop not working on new laptop

The 10 Pro key I tried using on my new laptop was from my old laptop. It is the only key of 10 Pro I have.

As stated earlier, I upgraded my old laptop from 8.1 Pro to 10 Pro back in 2015 via the free upgrade Microsoft offers to windows users. I did not pay anyone anything for the upgrade.

 

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