Wordpress custom post template is not valid

Question

I created a custom type name 'feed', then create some template files as single-feed.php, feed.php, taxonomy.php and archive-feed.php but all of them don't work. I get error "ERROR: This is not a valid feed template." Here is my code

  add_action( 'init', 'create_posttype' );
  function create_posttype() {
     register_post_type( 'feed',
     array(
         'labels' => array(
         'name' => __( 'Feed' ),
         'singular_name' => __( 'Feed' ),   
         'not_found' =>  __('No feed found'),
         'not_found_in_trash' => __('No feed found in Trash')
         ),
         'public' => true,
         'has_archive' => true,
         'rewrite' => array('slug' => 'feed','with_front'=>FALSE),
         'supports' => array('title','author', 'editor')
       )
    );
     flush_rewrite_rules();
 }
 register_taxonomy("feedgroup", array("feed"),
 array("hierarchical"=> true, "label" => "Feed Group", "singular_label" => "Feed", "rewrite"=>    true,'query_var' => true,'taxonomies'=>array('post-tag','feedgroup'),'slug'=>'feed'));

Answer 1

feed is a reserved name and should not be used by themes or plugins.

There is no work around to this problem. The only solution you have is to rename your custom post type to maybe feeds

You can get a list of reserved names here. Just a note, although this is on the register_taxonomy page, this list applies side wide for any naming convension, not just taxonomies