diff --git a/src/os/win32/sigar_os.h b/src/os/win32/sigar_os.h
index de626e53..155d174a 100644
--- a/src/os/win32/sigar_os.h
+++ b/src/os/win32/sigar_os.h
@@ -67,8 +67,12 @@ static __inline sigar_uint64_t FileTimeToTime(FILETIME *ft)
                                         lpw, -1, (LPSTR)lpa, chars, \
                                         NULL, NULL))
 
+#ifdef SIGAR_USING_MSC6
 /* iptypes.h from vc7, not available in vc6 */
 #include "msvc_iptypes.h"
+#else
+#include "iptypes.h"
+#endif
 
 /* from wtsapi32.h not in vs6.0 */
 typedef enum {