Failed in build

I followed the instruction to change the 5th line in MengeCS.csproj file, to something like "..\Menge\Menge-master\projects\VS2015\Menge\build\lib" (since I use visual studio to build Menge and Plugin project). However, the error thrown out is "could not find ..\MengeCS\bin\Debug\MengeCS.dll". MengeCS.dll is the file we are supposed to generate in this project. How to fix this error?