@VictorLerp asked me to add some info on this on the forums so I’m appending it here since the thread already exists and is findable.
As of 4.24, Datasmith is now part of the main engine instead of Unreal Studio. Datasmith is dependent on a number of header files which are normally included in the SDKs for the software Datasmith is meant to help streamline UE4 workflows for. These missing files will cause compiling the engine to fail:
SketchUpAPI/geometry.h
iparamb2.h
geometry.h is from Sketchup obviously, and is probably available somewhere.
But iparamb2.h is from the 3DSMax SDK, and when I looked into it, it appears that that SDK is only available as part of a subscription to 3DSMax.
Basically these dependencies mean that the UE4 engine can no longer be compiled just with the stuff included in the engine any more unless you also install some other SDKs which you may not even have access to. I don’t know if these files are redistributable, but either they should be included or the datasmith stuff should really be wrapped in some #IFDEFs or something to remove the dependency unless the user actually has access to the required files.