error C2509: 'GetMessageMap' : member function not declared in 'CMyWnd'

*.h->

DECLARE_MESSAGE_MAP()

*.Cpp->

BEGIN_MESSAGE_MAP(MyMultiMonitorTool, CDialog)

//{{AFX_MSG_MAP(MyMultiMonitorTool)

// NOTE: the ClassWizard will add message map macros here

//}}AFX_MSG_MAP

END_MESSAGE_MAP()