-#if _WIN32_WINNT < 0x0502
-/* Required for Vectored Exception Handling.
- Interlocked* functions are also not available in XP SP1 and below
-*/
-#undef _WIN32_WINNT
-#define _WIN32_WINNT 0x0502
-#endif /* _WIN32_WINNT < 0x0502 */
+#if _WIN32_WINNT < 0x0600
+#error "Mono requires Windows Vista or later"
+#endif /* _WIN32_WINNT < 0x0600 */