Loop posts without any taxonomy

One solution would be to give a value of “none” to your posts without any post group, similarly as you have “uncategorized” posts in WP Categories.

Alternatively… I haven’t checked it, but why don’t you try to make another WP_QUERY like this:

new WP_Query( array( 'post_type' => 'page', 'page_group' => '' ) )

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)