Network Direct SDK/DDK may be obtained as a nuget package (preferred) from: https://www.nuget.org/packages/NetworkDirect or downloaded from: https://www.microsoft.com/en-us/download/details.aspx?id=36043 on page press Download button and select NetworkDirect_DDK.zip. Extract header files from downloaded NetworkDirect_DDK.zip:\NetDirect\include\ file into this directory, or add path to NetDirect headers into VS include paths