diff --git a/src/plugins/platforms/windows/qtwindows_additional.h b/src/plugins/platforms/windows/qtwindows_additional.h
index 3465d4ab1e..3c7211cb71 100644
--- a/src/plugins/platforms/windows/qtwindows_additional.h
+++ b/src/plugins/platforms/windows/qtwindows_additional.h
@@ -65,7 +65,9 @@
 #    define COLOR_MENUBAR     30
 #    define CF_DIBV5 17
 
+#if !defined(CO_E_NOT_SUPPORTED)
 #define CO_E_NOT_SUPPORTED               _HRESULT_TYPEDEF_(0x80004021L)
+#endif
 
 #define IFMETHOD HRESULT STDMETHODCALLTYPE
 #define IFACEMETHODIMP STDMETHODIMP