求助,求VC++6.0大神指导 - 编程论坛

为什么在VC++6.0中用MFC创建windows窗口程序编译通过，打开EXE文件却没反应？？？
程序如下：
#include"afxwin.h"       //MFC程序库

class CMinMFCApp:public CWinApp        //窗口类

{

public:
    virtual BOOL Initlnstance();

};

class CMainWnd:public CFrameWnd
{

protected:
afx_msg void OnLButtonDown(UINT nFlags,CPoint point);
afx_msg void OnRButtonDown(UINT nFlags,CPoint point);
DECLARE_MESSAGE_MAP();

};

BEGIN_MESSAGE_MAP(CMainWnd,CFrameWnd)
ON_WM_LBUTTONDOWN()
ON_WM_RBUTTONDOWN()
END_MESSAGE_MAP()

void CMainWnd::OnLButtonDown(UINT nFlags,CPoint point)
{
    CString szAboutLeft=" 这是一个最小的WindowsMFC程序.\n你按下了鼠标左键！";
    ::MessageBeep(MB_ICONINFORMATION);

    ::MessageBox(GetSafeHwnd(),szAboutLeft,"About",MB_OK|MB_ICONINFORMATION);

    CFrameWnd::OnLButtonDown(nFlags,point);
}

void CMainWnd::OnRButtonDown(UINT nFlags,CPoint point)
{
    CString szAboutRight=" 这是一个最小的WindowsMFC程序.\n你按下了鼠标右键！";
    ::MessageBeep(MB_ICONINFORMATION);

    ::MessageBox(GetSafeHwnd(),szAboutRight,"About",MB_OK|MB_ICONINFORMATION);

    CFrameWnd::OnRButtonDown(nFlags,point);
}

BOOL CMinMFCApp::Initlnstance()
{
CMainWnd*pFrame = new CMainWnd;

pFrame->Create(0,_T("另一个小MFC程序"));
pFrame->ShowWindow(SW_SHOWMAXIMIZED);

pFrame->UpdateWindow();
AfxGetApp()->m_pMainWnd=pFrame;
return TRUE;
}

CMinMFCApp MyApp;
是哪里出问题了？