title: Get authors post in wordpress with co-author plus installed
body: <p>I want to list all posts, a user is assigned as author.
  We are using the plugin, co-authors plus, which allows to assign multiple authors to a single post.
  The function <code>&lt;?php $user_post_count = count_user_posts( $userid ); ?&gt;</code> returns the correct number of posts, the user is assigned to.
  But when trying to list all the posts, with The loop only the post which initially were created by that user are shown.</p>
  
  <pre><code>query_posts( $args );
  
  if (count_user_posts($user-&gt;ID) == 0) {
      echo "No posts";
  }
  
  // The Loop
  while ( have_posts() ) : the_post();
      echo '&lt;li&gt;';
      the_title();
      echo '&lt;/li&gt;';
  endwhile;
  </code></pre>
  
  <p>Is there an other possibility to get all posts from an user or can we modify our existing code?</p>