Using just the VS2017.sln (i did it via cmd line build) will fail with
C:\dev\ext\TwainDSM\TWAIN_DSM\visual_studio\TWAIN_DSM_VS2017.vcxproj : warning : The build tools for v141 cannot be found. Install v141 to build using the v141 build tools.
Because the Solution is in fact a still a 2015 solution.
It might depend on your local VS2017/VS2015 installations, but it can be easily fixed by opening TWAIN_DSM_VS2017.sln and changing just
Using just the VS2017.sln (i did it via cmd line build) will fail with
C:\dev\ext\TwainDSM\TWAIN_DSM\visual_studio\TWAIN_DSM_VS2017.vcxproj : warning : The build tools for v141 cannot be found. Install v141 to build using the v141 build tools.
Because the Solution is in fact a still a 2015 solution.
It might depend on your local VS2017/VS2015 installations, but it can be easily fixed by opening TWAIN_DSM_VS2017.sln and changing just
# Visual Studio 14
to# Visual Studio 15
and everything works like a charm :)