--- addressbook/backends/groupwise/e-book-backend-groupwise.c
+++ addressbook/backends/groupwise/e-book-backend-groupwise.c
@@ -2020,7 +2020,7 @@ e_book_backend_groupwise_get_contact_list (EBookBackend *backend,
 						g_object_unref (contact);
 					}
 					g_ptr_array_free (ids, TRUE);
-					ids->len = 0;
+					ids = NULL;
 				}
 			}
 			else {