CreateWindow Problem

[Amon Ra]

    //create the window
    g_Hwnd = ::CreateWindow ( g_szClassName, 
        g_szCaption,
        WS_MINIMIZEBOX | WS_SYSMENU,
        CW_USEDEFAULT, CW_USEDEFAULT,
        300, 
        NULL,
        NULL,
        hInstance,
        NULL);

    if (g_Hwnd == NULL)
    {
        MessageBox (NULL, "Window Creation failed", "PAManipulator Error", MB_OK);
            return 0;
    } 

when i do this, it gives me the following errors:

C:\My Documents\C++ Projects (Clean + Efficient)\Parrallel Port Assignment\Init.cpp(45) : warning C4003: not enough actual parameters for macro 'CreateWindowA'
C:\My Documents\C++ Projects (Clean + Efficient)\Parrallel Port Assignment\Init.cpp(45) : error C2059: syntax error : ')'
Error executing cl.exe.