Compiler complains about a setting (throws an error) error: More than 1 Code Generation option speci


I have a working C and C for Cuda project that I want to call from a C# project

So I intend to discard the C/C++ parts and want to just create a .cubin file

however when I change “NVCC Compilation Type” in the CUDA C/C++ section of Properties to cubin I get the following error message

What else do i need to change ?

or is NVCC pre-reading my code and finding there is still some host code present ?

PS I already have a large amount of working C for Cuda so I don’t want to go down Cudafy approach at present.

Thanks in advance for any help.