diff --git a/reactos/include/psdk/shellapi.h b/reactos/include/psdk/shellapi.h
index d4224ecb108..cd4a6144ee4 100644
--- a/reactos/include/psdk/shellapi.h
+++ b/reactos/include/psdk/shellapi.h
@@ -22,7 +22,8 @@ extern "C" {
 #define SEE_MASK_HOTKEY	0x20
 #define SEE_MASK_NOCLOSEPROCESS	0x40
 #define SEE_MASK_CONNECTNETDRV	0x80
-#define SEE_MASK_FLAG_DDEWAIT	0x100
+#define SEE_MASK_NOASYNC	0x00000100
+#define SEE_MASK_FLAG_DDEWAIT	SEE_MASK_NOASYNC
 #define SEE_MASK_DOENVSUBST	0x200
 #define SEE_MASK_FLAG_NO_UI	0x400
 #define SEE_MASK_NO_CONSOLE	0x8000