diff --git a/media/mtransport/third_party/nrappkit/src/util/util.h b/media/mtransport/third_party/nrappkit/src/util/util.h
index 1bfa4eb615..1f93fb6ce8 100644
--- a/media/mtransport/third_party/nrappkit/src/util/util.h
+++ b/media/mtransport/third_party/nrappkit/src/util/util.h
@@ -68,7 +68,7 @@ int nr_reg_uint8_fetch_and_check(NR_registry key, UINT8 min, UINT8 max, int log_
 int snprintf(char *buffer, size_t n, const char *format, ...);
 // When using Windows Vista+ header files, inet_ntop is already defined 
 // with a different type modifier, so we don't redefine it
-#if defined(WIN_VER) && WIN_VER <0x0600 
+#if defined(WINVER) && WINVER <0x0600 
 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 #endif
 #endif