Running “bcdboot.exe c:\windows /l en-us”
returned a “Failure when attempting to copy boot files” error. And yes, I did check if the partition was active and it was. I heard that this issue was resolved by some by destroying the array, rebuilding it and installing the image again. I did so but with no further luck – unfortunately a huge waste of time over iLO and a slow connection (you probably know what I mean).
Turns out that the command which finally worked correctly was “bcdboot c:\Windows /s c: /l en-us” while running it from the WinPE drive.
The “/s” option according to the manual “Specifies an optional volume letter parameter to designate the target system partition where boot environment files are copied. The default is the system partition identified by the firmware.”
I guess the default system partition could not be properly identified thus all the fuss. Weird, I haven't found a reason for this. Didn't look deeper since I found a fix. Anyway, hope this helps!