Firstly, check if your application is build correctly. Go to Tools > Settings > Expert Settings > Build > Build Solution / Rebuild and check the Output window (View > Output) if your application is compiling and linking correctly. If yes, check the directory of your project for a .cpp file. From what it seems, this error is caused by a .cpp file that is missing. In order to add this file to your project, you need to click Add new item icon from top left or to press Ctrl + N key combination.
