title: Move WordPress posts and related taxonomy to custom post type & taxonomy
body: <p>I have a clean WordPress installation using Twenty Eleven, with no plugins or other modifications. The blog contains approximately 800 posts with related tags and categories. </p>
  
  <p>I'd like to move all these posts to a custom post type. By adding the following code to my functions.php my blog now has the custom post type installed and working perfectly.</p>
  
  <pre><code>//Add custom post type
  add_action( 'init', 'create_en_post_type' );
      function create_en_post_type() {
          register_post_type( 'en_post',  array(
              'labels' =&gt; array(
                  'name' =&gt; __( 'English Posts' ),
                  'singular_name' =&gt; __( 'English Post' )
              ),
              'public' =&gt; true,
              'menu_position' =&gt; 5,
              'rewrite' =&gt; array('slug' =&gt; 'en'),
              'supports' =&gt; array(
                  'title', 
                  'editor', 
                  'author', 
                  'excerpt', 
                  'comments', 
                  'custom-fields'
              )
          ));
      }
  
  //Add belonging custom taxonomy
  add_action( 'init', 'build_taxonomies', 0 ); 
      function build_taxonomies() { 
      register_taxonomy( 'english_categories', 'en_post', array( 'hierarchical' =&gt; true, 'label' =&gt; 'English Categories', 'query_var' =&gt; true, 'rewrite' =&gt; true ) );
      register_taxonomy( 'english_tags', 'en_post', array( 'hierarchical' =&gt; false, 'label' =&gt; 'English Tags', 'query_var' =&gt; true, 'rewrite' =&gt; true ) );
      }
  </code></pre>
  
  <p>Now all I need is to change the regular post type to my custom post type. I've managed to move the posts using the plugin <a href="http://wordpress.org/extend/plugins/convert-post-types/" rel="nofollow">Convert Post Types</a>, but my taxonomies aren't converted. </p>
  
  <p>I realize I could just create similar custom categories and assign the custom posts to them, but what about tags? How can I convert these (automatically, 1200 tags)?</p>
  
  <p>I've tried manually messing around in the database, but I can't make it work.</p>