I’ve recently installed some new roles on a windows 2012 core server. It took me about 3 days on and off to realise why, while I was specifying a wim on the 2012 Dvd, it wasn’t working. I was running Datacenter edition core and was pointing to the specific ID in the wim for this version.

However, I was being a spud. If the install core OS didn’t have the needed cabs, why did I think the core wim would? As soon as I pointed me install to the full gui wim (index 3 I believe) it worked a treat. There are plenty of articles on how to find the right wim index, so I wont link any here, but yeah really simple mistake but annoying