diff --git a/src/msw/window.cpp b/src/msw/window.cpp
index 02e5c2cfcf..bcad284c87 100644
--- a/src/msw/window.cpp
+++ b/src/msw/window.cpp
@@ -3662,7 +3662,8 @@ wxWindowMSW::MSWOnDrawItem(int WXUNUSED_UNLESS_ODRAWN(id),
     {
         wxMenuItem *pMenuItem = (wxMenuItem *)(pDrawStruct->itemData);
 
-        wxCHECK( pMenuItem->IsKindOf(CLASSINFO(wxMenuItem)), false );
+        wxCHECK_MSG( pMenuItem && pMenuItem->IsKindOf(CLASSINFO(wxMenuItem)),
+                         false, _T("MSWOnDrawItem: bad wxMenuItem pointer") );
 
         // prepare to call OnDrawItem(): notice using of wxDCTemp to prevent
         // the DC from being released
@@ -3719,7 +3720,8 @@ wxWindowMSW::MSWOnMeasureItem(int id, WXMEASUREITEMSTRUCT *itemStruct)
     {
         wxMenuItem *pMenuItem = (wxMenuItem *)(pMeasureStruct->itemData);
 
-        wxCHECK( pMenuItem->IsKindOf(CLASSINFO(wxMenuItem)), false );
+        wxCHECK_MSG( pMenuItem && pMenuItem->IsKindOf(CLASSINFO(wxMenuItem)),
+                        false, _T("MSWOnMeasureItem: bad wxMenuItem pointer") );
 
         size_t w, h;
         bool rc = pMenuItem->OnMeasureItem(&w, &h);