C++ – Error C1083 Cannot open include file: ‘opencv2\opencv.hpp’ in VS 2015

I am trying to run the simple test code below on Visual Studio 2015 with OpenCv 3.1 on windows 10.

#include <opencv2\opencv.hpp>
using namespace cv;
int main()
{
namedWindow("win");
waitKey(0);
return 1;
}

But i get

Error C1083 Cannot open include file: 'opencv2\opencv.hpp': No such
file or directory

I have added the Path C: \ opencv \ build \ x64 \ vc14 \ bin to System variable in the Windows Environment variables.

Also in Visual studio I have set the Include Directories C:\opencv\build\include;$(IncludePath) under Project properties > VC++ Directories and also the Linker > Input Additional Dependencies set to opencv_world310d.lib (Debug)

I also have the following setting:

Executable Directories – C:\opencv\build\x64\vc14

Library Directories – C:\opencv\build\x64\vc14\lib

Additional Library Directories – C:\opencv\build\x64\vc14\lib

Please help me resolve this error.