export in DLL

I created a DLL file, has the export function as follow:

==========DLL.CPP==========
__declspec(dllexport) void ProcessMessage(void)
{
      AFX_MANAGE_STATE(AfxGetStaticModuleState());
      return;
}

==========APP.CPP==========
CMain::CMain()
{
  void *processMsg;

  HINSTANCE hDll = LoadLibrary("DLL.DLL");

  if (hDll == NULL)
  {
    AfxMessageBox("WARNING! Can't load DLL.DLL", MB_OK | MB_ICONSTOP, 0);
    _exit (0);
  }
 
  processMsg = (void*) GetProcAddress(hDll,"ProcessMessage");

  if (processMsg == NULL)
  {
    DWORD err = GetLastError();
    wsprintf((LPSTR)sztmp, "%s%d", "Error Code:", err);
    AfxMessageBox(sztmp, MB_OK | MB_ICONSTOP, 0);
    _exit(0);
  }
}

I can load the DLL without any problem. But I always got GetProcAddress wrong, with error code 126, i.e. module not found. What did I go wrong?
tangkhAsked:
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tangkhAuthor Commented:
Edited text of question
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jkrCommented:
Simply declare the function as
extern "C" __declspec(dllexport) void ProcessMessage(void)
and list it in your .def file (if it isn't listed here using the same name as in the call to 'GetProcAddress()', some linkers will probably prepend an underscore - to check this and the actual export name, you can use 'QuickView' from the Explorer's context menu).
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dekoayCommented:
Hi tangkh!

You need to attach  *.DEF file during your program compilatio so that the other program that used this DLL could identify the module. If u do not know the format, then just follow the format below and save it as *.def

LIBRARY <DLL name>
DESCRIPTION
EXPORTS  
              <function name to export> @1

Dekoay
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