I have a legit copy of Windows 8 Pro and I got a code a while back to get the free upgrade for the Windows Media Centre version too.
So I installed Windows 8 with my Pro key then tried to upgrade to the Media Centre version too.
It won't activate though, and the error code it throws up doesn't really shed any light on the matter either, can't see anything relevant relating to it on Google at all...
Error code: 0xC004C400
Error description: Unable to find a detailed error description.
Unknown facility code of:0x04 (04L)
Facility error: 0xC400 (50176L)
I kinda wish I could just revert back to the Pro version and forget Media Centre without having to install from scratch again.