diff --git a/reactos/lib/user32/windows/text.c b/reactos/lib/user32/windows/text.c
index e1bfce0bf5c..1c1fc19042c 100644
--- a/reactos/lib/user32/windows/text.c
+++ b/reactos/lib/user32/windows/text.c
@@ -53,6 +53,7 @@ WINAPI
 CharLowerA(LPSTR x)
 {
     if (!HIWORD(x)) return (LPSTR)tolower((char)(int)x);
+    CharLowerBuffA(x, strlen(x));
 /*
     __TRY
     {