Hi,
A new motherboard will cause a Digital License to be invalid.. One license per machine, and a new motherboard is considered a new machine.. The license is linked to the Hardware ID of the motherboard..
If a Retail License, it can be transferred to a new machine once it is deactivated on the original.. Unfortunately I don't have a clue as to how that is done once the machine has been disassembled..
From what I've read, a retail digital license is tied to your microsoft account for a particular device (being digital, there's no key to enter, nor is there a key to deactivate). That's what I have.
The built-in method to activate after changing hardware is to use the troubleshooter and choose the option "I changed hardware on this device recently". That opens a page with the device(s) are linked to your microsoft account so you can choose the old device to be replaced with the new one, and subsequently activate the license.
The issue is, my old licensed PC does not appear in that list to switch the license from. I see a completely different PC in that list, (a laptop that is separately licensed via OEM) that has nothing to do with this system or my previous desktop. Presumably, I should see both my old PC there and I don't.
Support was very adamant that: 1) they see I have a retail licensed version and 2) they state there is a "global issue" causing activation problems for many people. If that's true, I am trying to find out more information since they couldn't give me a resolution on the phone at that time.