In your %Temp% folder you’ll find some logs that start with UE4_Prerequisites. To access this folder simply type %Temp% into the Windows File Explorer file path bar. Zip those files up, attach to the thread, and I’ll have a look. Judging by your previous post, I suspect we’ll find that DirectX is having an issue installing again. If that is the case, we’ll have to apply a workaround somewhat similar to the one you used to get the Launcher installed. I’ll work on getting the steps for that workaround drafted up while I waiting on your logs.