diff --git a/src/frontends/qt4/Dialog.cpp b/src/frontends/qt4/Dialog.cpp
index c26b38f468..15e96136a4 100644
--- a/src/frontends/qt4/Dialog.cpp
+++ b/src/frontends/qt4/Dialog.cpp
@@ -19,7 +19,7 @@
 #include "FuncStatus.h"
 #include "LyXFunc.h"
 
-#include "support/Debug.h"
+#include "support/debug.h"
 
 #include <string>