diff --git a/src/insexpand.c b/src/insexpand.c
index 1051ae1..926b351 100644
--- a/src/insexpand.c
+++ b/src/insexpand.c
@@ -4355,7 +4355,7 @@
     funcname = get_complete_funcname(ctrl_x_mode);
     if (*funcname == NUL)
     {
-	semsg(_(e_notset), ctrl_x_mode == CTRL_X_FUNCTION
+	semsg(_(e_option_str_is_not_set), ctrl_x_mode == CTRL_X_FUNCTION
 		? "completefunc" : "omnifunc");
 	return FAIL;
     }