a problem with BitmapEx.h

i write this code but it gives an error. why it does not include the header file?

coding:

#include "BitmapEx.h"
CBitmapEx bitmapEx;
bitmapEx.Load(_T("En开发者_开发问答ter bitmap source file path here..."));
bitmapEx.Rotate(45);
bitmapEx.Sepia();
bitmapEx.Scale(50, 50);
bitmapEx.Draw(hDC);
bitmapEx.Save(_T("Enter bitmap destination file path here..."));

error: Cannot open include file: 'BitmapEx.h': No such file or directory

Clearly, like the error message tells you, it cannot find the file. Did you spell the name correctly? Is it in the current directory, or if not, in the current include path?