I ran into this issue…when trying to activate an expired evaluation copy of Server 2016. It wouldn’t let me update the product key.
Error
“Error: 0xC004F069 On a computer running Microsoft Windows non-core edition, run ‘slui.exe 0x2a 0xC004F069’ to display the error text”
Solution
Find available target editions
DISM.exe /Online /Get-TargetEditions
Change your target edition
DISM /online /Set-Edition:ServerStandard /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX /AcceptEula