Hi,
Could you post the two files listed in the output, please:
C:/dev/Unreal/Projects/MyProject5/Intermediate/Build/Win64/Inc/MyProject5/GeneratedMeshComponent.generated.h
C:/dev/Unreal/Projects/MyProject5/Intermediate/Build/Win64/Inc/MyProject5/GeneratedMeshComponent.generated.h.conflict
This will better allow us to diagnose the problem.
Thanks,
Steve