把 targetver.h 里面的 0x0600 修改为 0x0500(win2k) or 0x0501 (xp)
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#ifndef WINVER // Specifies that the minimum required platform is Windows Vista.
#define WINVER 0x0501 // WinXP
#endif
#ifndef _WIN32_WINNT // Specifies that the minimum required platform is Windows Vista.
#define _WIN32_WINNT 0x0501 // WinXP
#endif