Create a “Page Doesn’t Exist” message

If your theme didn’t come prepackaged with a 404.php it’s easy to create one. What theme are you currently using so that I can be more specific?

Try this,

<?php get_header(); ?>

<div id="content">

<?php include(TEMPLATEPATH."/l_sidebar.php");?>

<div id="main"><div class="entry">

<h3>ERROR 404 - NOT FOUND</h3>
<p>&nbsp;</p>
<p>YOUR CUSTOM ERROR MESSAGE HERE</p>

</div></div>

<?php include(TEMPLATEPATH."/r_sidebar.php");?>

</div>

<?php get_footer(); ?>

Paste that in a plain text editor such as notepad, call it 404.php and upload it to your themes folder.