Doxygen won't process main.cpp

So I'm new to using Doxygen and I was able to get it to work smoothly. I was able to document my classes and structs and it generates the HTML files perfectly. The issue I'm running into is it won't parse my main.cpp file. All the classes and structs have their own .h and .cpp files and they process fine. How do I get Doxygen to make the documentation for main.cpp? It doesn't have a .h file as this is where the program starts and ends. I wouldn't even know what to put in the .h file for main. I'm using Doxywizard in Windows.

Edit:

I put this in main and it generates a main page:

/**
@mainpage

This is a test application.

@author Alex
@date 10/21/2010
@version 1.0
*/

But then farther down the file where the function prototypes are I have this and it doesn't get parsed:

/**
@brief Error handler for the PDF writer.

It does nothing. It just has to exist.
*/
void error_handler (HPDF_STATUS   error_no,
                    HPDF_STATUS   detail_no,
                    void         *user_data)
{
}

I put this at the top of main.cpp and it worked. Go figure.

/**
@file main.cpp
*/