Please humor me one more time. 
This subject has come up times before, yet never with a clear understanding of the answer. Basically, when you install and activate the Windows operating system it shall stay on the PC for the rest of its life. Unless the computer out right fails and has to be replaced.
Now let's take that a little bit further. The old computer does not completely fail, it is just getting to the point where it does not work as well as it should. You have another computer in your inventory that has better characteristics but does not have an activated new version of Windows. Specifically, Windows 10.
Now here I am. 
To be more specific, the computer I want to use is a Dell 745 which I repaired and got it to work with Windows XP. That particular model is always certified for Windows XP, so I had no trouble installing the standard Dell version of Windows XP three. It is legal. But I need Windows 10 home version.
Yer, now I want to use Windows 10 on that 745.I have Windows 10 on an older GX520 that is no longer suitable for what I want to do. Rather than add more hardware to upgrade the old computer, I would rather just transfer my Windows 10 on to the Dell 745. Unfortunately, I never did put Windows 10 on that Dell 745. Just now I did put Windows 10 on it, but I do not have a product key to activate.
As mentioned earlier, this sort of question has been answered before but the answer never seems to be very clear and concise. Is there another way I can install Windows 10 off of another computer and then install it on this Dell 745 . But, here is the gotcha, May I make that computer the registered computer for that copy of Windows 10?
The general the answer should be no,
you cannot transfer Windows 10 from one computer to another. However,
I thought there could be some exception to this if you were to call up Microsoft directly and talk to one of their technicians and get permission to make the transfer. Perhaps that was true at one time, but is no longer the current policy of Microsoft.
Microsoft's EULA does not clarify how one could transfer the operating system to another computer. It seems to say that you cannot do such a thing. If that is so, then I'm stuck.
But the question is this: Is there some legal practical way to transfer Windows 10 from one computer to another? If Microsoft would have used something like a dongle this would not be such an issue. (Maybe, or maybe not.) Anyway, the current situation is that when you login to the Internet Windows checks to see if your computer is the one that is associated with the installed version of Windows 10. Or maybe something like that.
So I'm asking again, it's a some legal way to make an exception to the EU LA when a user wishes to upgrade to a better computer and stop using Windows 10 on the older computer.
Thank you for your patience.What's the answer?
