diff --git a/dll/win32/comctl32/combo.c b/dll/win32/comctl32/combo.c
index 9b694dcbf7b..135eb206465 100644
--- a/dll/win32/comctl32/combo.c
+++ b/dll/win32/comctl32/combo.c
@@ -1890,8 +1890,11 @@ static LRESULT CALLBACK COMBO_WindowProc( HWND hwnd, UINT message, WPARAM wParam
     case WM_SYSKEYDOWN:
         if ( KEYDATA_ALT & HIWORD(lParam) )
             if( wParam == VK_UP || wParam == VK_DOWN )
+            {
                 COMBO_FlipListbox( lphc, FALSE, FALSE );
-        return  0;
+                return  0;
+            }
+        break;
 
     case WM_KEYDOWN:
         if ((wParam == VK_RETURN || wParam == VK_ESCAPE) &&