I was able to build the source version of UE4 4.13.0 release earlier but am unable to do so anymore because of an error regarding certain pre-compiled
The error in VS 2015 is pasted below
C:\Users\Valued Customer\Documents\thirteen\Engine\Intermediate\Build\Win64\UnrealHeaderTool\Development\Core\PCH.CorePrivatePCH.h.cpp(1): fatal error C1085: Cannot write precompiled header file: ‘C:\Users\Valued Customer\Documents\thirteen\Engine\Intermediate\Build\Win64\UnrealHeaderTool\Development\Core\CorePrivatePCH.h.pch’: The request could not be performed because of an I/O device error.