diff --git a/nncmpp.c b/nncmpp.c
index 9c2efee..6214345 100644
--- a/nncmpp.c
+++ b/nncmpp.c
@@ -2536,6 +2536,7 @@ app_process_action (enum action action)
 		app_invalidate ();
 		return true;
 	default:
+		print_error ("can't do that here: %s", g_action_descriptions[action]);
 		return false;
 
 	case ACTION_MULTISELECT:
@@ -2666,6 +2667,7 @@ app_editor_process_action (enum action action)
 		g.editor.on_end = NULL;
 		return true;
 	default:
+		print_error ("can't do that here: %s", g_action_descriptions[action]);
 		return false;
 
 	case ACTION_EDITOR_B_CHAR: