[Theme Horse Support Team]

Hi all,

Creating the same structure in the child theme will not over ride the parent theme. First of all you need to unhook the function and then customize the code. We will post a simple example how to unhook to functions:-
Create a two files styles.css and functions.php

Under style.css add this following code.

/*
Theme Name: interface Child Theme
Author: Self-Help WordPress User
Template: interface
*/

@import url("../interface/style.css"); 

Under functions.php file

unhook functions

// Unhook default Thematic functions
function unhook_thematic_functions() {
    // Don't forget the position number if the original function has one

remove_action( ‘interface_404_content', ‘interface_display_404_page_content', 10 );

}
add_action('init','unhook_thematic_functions'); // removes the header content by using hook interface_header

add_action( ‘interface_404_content', ‘interface_child_display_404_page_content', 10 );
/**
 * function to show the footer info, copyright information
 */
 
 
function interface_child_display_404_page_content() {      ?>   
<div id="content">
		<header class="entry-header">
			<h1 class="entry-title"><?php _e( 'Error 404-Page NOT Found', ‘interface’ ); ?></h1>
		</header>
		<div class="entry-content clearfix" >
			<p>Thank you</p> 
		</div><!-- .entry-content -->
	</div><!-- #content -->
  <?php 
}

If you are still unable to fix it then you need to hire a developer to fix it.

Thank you!