hi. I have an MFC based app which uses a printer to print.

After install printer named "HP Lazer Jet 4000 PCL 6".
When I print it with "Test Page", the page can be printed out successfully( or by other program such as word 2000 ). So I think
the printer is installed properly.

But In my app I will use this printer to print pages.
CDC * CreatePrinterDC( LPCTSTR lpszPrinter )
        HANDLE hPrinter = NULL ;
        if (!OpenPrinter((LPTSTR)lpszPrinter , &hPrinter, NULL))
	return NULL;

        DWORD dwErr = GetLastError() ; //  dwErr == 0 
        // A zero for last param returns the size of buffer needed. 
        // Get the printer settings and reset with default values.
         int nSize = DocumentProperties(NULL, hPrinter, (LPTSTR)
lpszPrinter , NULL, NULL, 0);

          dwErr = GetLastError() ; //  dwErr == 6 
          if(nSize < 0)
                ClosePrinter( hPrinter ) ;
                return NULL;

           // other codes for set the default behaviors for this
           // printer and return the printer DC.
From MSDN, "6" means the handle is Invalid, But the function call
OpenPrinter() succeeds.

I don't the reason. who has ideas ?