diff --git a/apps/openmw/mwgui/messagebox.cpp b/apps/openmw/mwgui/messagebox.cpp
index 9cb778ea2..cdbcf784d 100644
--- a/apps/openmw/mwgui/messagebox.cpp
+++ b/apps/openmw/mwgui/messagebox.cpp
@@ -12,6 +12,8 @@
 #include "../mwbase/inputmanager.hpp"
 #include "../mwbase/windowmanager.hpp"
 
+#undef MessageBox
+
 namespace MWGui
 {