diff --git a/reactos/subsystems/win32/win32k/ntuser/window.c b/reactos/subsystems/win32/win32k/ntuser/window.c
index 77b2aaa4f84..aa9509fcd0c 100644
--- a/reactos/subsystems/win32/win32k/ntuser/window.c
+++ b/reactos/subsystems/win32/win32k/ntuser/window.c
@@ -30,7 +30,7 @@
 
 #include <w32k.h>
 
-//#define YDEBUG
+#define NDEBUG
 #include <debug.h>
 
 /* dialog resources appear to pass this in 16 bits, handle them properly */