Compiler output.
Error 1 error C1010: unexpected end of file while looking for precompiled header. Did you forget to add '#include "stdafx.h"' to your source? C:\Users\Cathal\Documents\Visual Studio 2013\Projects\Go\Go\go.c 367 1 Go
Was working fine then all of a sudden the compiler starts asking for the precompiled headers which I turned off in the project properties.
ANSWER
I figured out that one of the projects (two projects in solution) had different configuration settings that was screwing the solution up. Can't mix and match of course. I wish VS would highlight this.