Windows 10: Previously used license keys, which one to re-use for a VM

I always been buying retail versions of Windows.
Right now I have a few licenses from v7/8/8.1 upgraded to W10 and a single new retail license (USB thumbdrive) of Windows 10.

The new retail version I use on my host pc.
The 'upgraded' versions I have used/installed/uninstalled before on another pc or as VM, but all deactivated.

I have the first/original v7/v8-license keys, but probably they became null and void after they have been upgraded to W10(?)

There is 1 VM running using some 'upgraded' license key.
I'd like to create a new, 2nd, VM, using another key.


Here is the problem:
Frankly, I have no idea how to proceed.
I may install CU version from USB (media creation tool), but likely at one point in time I may need to enter a key.
However, I don't know which key has been used for the existing VM, i.e. which of the remaining upgraded keys are 'free' to use.

Any suggestions as to how to proceed. Is this a kind of trial and error and see which key is accepted?

Thanks
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:)

 

Transfer win 10 license

Little confusing here - I'm burning a Win 10 license on a VM on my laptop now. I want to repurpose the license from this VM to a new brand new VM that I plan on building by importing my daughters desktop. I want to keep her desktop live - so I need to
re-use the license. Problem is - I don't know if I have the original product key that I used to activate this VM. I know I can free the activation from this VM - but how do I reactivate under a fresh VM w/o the product key. Thanks....

 

Can I use Windows 10 VM (legal license) on two different Hosts (VirtualBox)?

I know that a VM is considered like a physical computer and requires its own license, but I hadn't previously considered what happens when you move a VM to another computer. It seems logical that you can't have the same VM licensed on two computers. But
can you move a VM from one computer to another while maintaining the VM's license?

 

Original keys always remain valid.

You can still activate Windows 10 with 7/8 keys.

So just install and use any key - it may object key is in use, if so try next one.

Once it works, make note of key and which vm.

 

Many thanks indeed! Truly appreciate the quick feedback.
Windows is now installing in VM in the background using a Windows 8 key.
Again, thanks!
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