So I have an Alienware X51 R2 that I bought in September 2014 (with Windows 8), and upgraded to Windows 10 in July like everyone else. Things have been fine until a few days ago. I went to the Dell site to check if there were any driver updates (I was having some graphics card issues), and there were 4 of them (1 for the BIOS, the other 3 for graphics cards). The BIOS update went fine until it made me restart -- I had to go into the BIOS settings and change the mode from "Legacy" to "UEFI" -- because keeping it on "Legacy" just gave me a black screen of death.
This worked, but now Windows thinks I need to activate Windows 10, even though I did that already when it was originally released. In the Activation section of the settings, it gives error code 0xc004c003, which I've googled and seems to mean I need to start all over again with Windows 8.
Do I really need to do that, or is there some other setting or BIOS tweak I can try?
It seems like Windows 10 thinks you've got a new motherboard, hence a new system and has therefore deactivated the Windows license. Windows 10 activation license is tied to your hardware, and changing components like the motherboard (even to the same model) will deactivate the license. This should not happen on a mere BIOS change but unfortunately seems to be the case in this situation.
Not sure if reverting to the old BIOS will help.
That's what I was afraid of.
I did some more googling, and found comments by others w/ this issue that they got a new license key by using Windows 10's Chat Support app. I did that today and explained my situation, and since I was able to provide my old Windows 8 key, they remotely accessed my PC (with my permission) to try and fix the deactivation. In the end they gave me a new key, so all is fixed 🙂