Adding custom post type support in functions.php file to show custom posts types in category, tags & archives.

function.php

/*
display / Show custom post types posts in Archive, tags & categories.
*/

	function query_post_type($query) {
  if(is_category() || is_tag()) {
    $post_type = get_query_var('post_type');
    if($post_type) {
      $post_type = $post_type;
    } else {
      $post_type = array('nav_menu_item','post','custom_posttype1', 'custom_posttype2', 'custom_posttype3', 'custom_posttype4');
    }
    $query->set('post_type',$post_type);
    return $query;
  }
}
add_filter('pre_get_posts', 'query_post_type');