diff --git a/apps/openmw/CMakeLists.txt b/apps/openmw/CMakeLists.txt
index bb62c0044..492c3869b 100644
--- a/apps/openmw/CMakeLists.txt
+++ b/apps/openmw/CMakeLists.txt
@@ -50,6 +50,7 @@ set(GAMEGUI_HEADER
     mwgui/dialogue_history.hpp
     mwgui/window_base.hpp
     mwgui/stats_window.hpp
+    mwgui/messagebox.hpp
 )
 set(GAMEGUI
     mwgui/window_manager.cpp