错误1error C1189: #error : This file requires _WIN32_WINNT to be #defined at least to 0x0403. Value

错误 1 error C1189: #error :  This file requires _WIN32_WINNT to be #defined at least to 0x0403. Value 0x0501 or higher is recommended.c:\program files\microsoft visual studio 10.0\vc\atlmfc\include\atlcore.h35 1 VFD 问题的解决办法

最近拿到一个别人的工程，是使用VS.net创建的，而我的机器上只有vs2010，于是用自带的转换工具将它转换成vs2010的工程，转换之前我就很担心，怕转换完后会出问题，但是没有办法，我实在是不想再安一个vs.net了。

  转完后果不其然真出了问题，在重新build工程时，报了一大堆错误，其中第一个就是“fatal error C1189: #error : This file requires _WIN32_WINNT to be #defined at least to 0x0403. Value 0x0501 or higher is recommended”，然后看错误的来源，竟然是atlcore.h，这我就无语了，这是mfc自带的文件，出错的可能性基本上为0，于是只好去请教谷大叔，发现很多人都遇到了这个问题，看了几篇博客和帖子后，大概明白了，应该是_WIN32_WINNT这个宏对应定义的系统的版本号，如果太低的话，编译器就会认为代码无法在当前的系统上编译。

  说了原因，下面是修改方法，就是在stdafx.h文件中修改相关的定义，修改完后的效果应该如下：

// stdafx.h : include file for standard system include files,
// or project specific include files that are used frequently,
// but are changed infrequently


#pragma once


#ifndef VC_EXTRALEAN
#define VC_EXTRALEAN // Exclude rarely-used stuff from Windows headers
#endif


// Modify the following defines if you have to target a platform prior to the ones specified below.
// Refer to MSDN for the latest info on corresponding values for different platforms.
#ifndef WINVER // Allow use of features specific to Windows 95 and Windows NT 4 or later.
#define WINVER 0x0501// Change this to the appropriate value to target Windows 98 and Windows 2000 or later.
#endif


#ifndef _WIN32_WINNT // Allow use of features specific to Windows NT 4 or later.
#define _WIN32_WINNT 0x0501// Change this to the appropriate value to target Windows 98 and Windows 2000 or later.
#endif


#ifndef _WIN32_WINDOWS // Allow use of features specific to Windows 98 or later.
#define _WIN32_WINDOWS 0x0501 // Change this to the appropriate value to target Windows Me or later.
#endif


#ifndef _WIN32_IE // Allow use of features specific to IE 4.0 or later.
#define _WIN32_IE 0x0601// Change this to the appropriate value to target IE 5.0 or later.
#endif


#define _ATL_CSTRING_EXPLICIT_CONSTRUCTORS // some CString constructors will be explicit