diff --git a/reactos/dll/win32/user32/include/user32.h b/reactos/dll/win32/user32/include/user32.h
index 5d998a469cc..9f5472e1a00 100644
--- a/reactos/dll/win32/user32/include/user32.h
+++ b/reactos/dll/win32/user32/include/user32.h
@@ -21,7 +21,7 @@
 #include <windows.h>
 #include <windowsx.h>
 #include <winnls32.h>
-#include <Strsafe.h>
+#include <strsafe.h>
 #include <ndk/cmfuncs.h>
 #include <ndk/kefuncs.h>
 #include <ndk/obfuncs.h>