diff --git a/platform/win32/contiki-conf.h b/platform/win32/contiki-conf.h
index 9344c26b7..0e6f10c1e 100644
--- a/platform/win32/contiki-conf.h
+++ b/platform/win32/contiki-conf.h
@@ -38,8 +38,8 @@ typedef   signed char    int8_t;
 typedef unsigned char   uint8_t;
 typedef   signed short  int16_t;
 typedef unsigned short uint16_t;
-typedef   signed long   int32_t;
-typedef unsigned long  uint32_t;
+typedef   signed int    int32_t;
+typedef unsigned int   uint32_t;
 
 /* These names are deprecated, use C99 names. */
 typedef unsigned char   u8_t;