Issue with 404

I’ve looked through the forum and can’t find a similar problem.

I have an odd page being served on files that should not exist. I have a 404.php in the theme which is not being called, instead the page that is served is a truncated sidebar, and the footer. There is no header.

I have try the correct direction in .htaccess which does not work, I have even tried to apply a 404 rule to a static page outside of wordpress – this does not work.

The only thing I have done that is not standard is directed the page to specific templates from with the index.php file of the theme, however I have been through all of these, put some identifying text in each, and still cannot trap/identify the template that is being served on pages that are not found.

The website is http://www.eantics.co.uk – if you type any none existent page like /notexist.php from there you will see the output I am referring to.

Advice & Help appreciated

Ollie