Page Not Found Custom 404 Error Page with Site Map Sample Text

hi
i have a zencart that is ok for gategories but when you drill down to open up individual products i get the following error message

Page Not Found

Custom 404 Error Page with Site Map Sample Text�...

If i click on the rss on my site in question this is what i read
http://goodsexguide.co.uk/store en Copyright (c) 2010 derek53 derkcfitch################## (derek53) derkcfitch################## (derek53) Wed, 31 Dec 1969 18:00:00 -0600 Zen-Cart v. v 2.1.4 14.02.2008 15:26 RSS 2.0 Feed 1440

i have to say that i have paid someone to instal the rss and also the product by a product feed so i havent a clue where to look or what to do. I feel like falling onto my sword !!!

Please can someone offer advice

many thanks

What version of zen cart are you using?
Please list all mods you have used?

Read this please:

http://www.zen-cart.com/index.php?main_page=product_contrib_info&products_id=860

haredo:

What version of zen cart are you using?
Please list all mods you have used?

Read this please:

I am using version 1.3.8a [Patched]

I personaly have used no mods, but the chap who installed the rss used the zencart mod and the instalation of this on my other sites has worked fine.

I will try the bug finder and see if that helps. many thanks for that

hi
found two lines of code and both lines that are referred to in the following are blank

[24-May-2010 06:48:49] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/sexguide/public_html/store/includes/languages/english.php:1401) in /home/sexguide/public_html/store/includes/init_includes/init_templates.php on line 78

[24-May-2010 06:48:49] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/sexguide/public_html/store/includes/languages/english.php:1401) in /home/sexguide/public_html/store/includes/modules/pages/page_not_found/header_php.php on line 16

Hope this means something as it doesnt to me

many thanks

derek53:

[24-May-2010 06:48:49] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/sexguide/public_html/store/includes/languages/english.php:1401) in ...
Problem is in your english.php
Looking up your error message in the FAQ area brings up this article: https://www.zen-cart.com/tutorials/index.php?article=87

Deleted the two empty lines that the error report highlighted. The error message page not found is still showing but there is no error report generated. I put back the two empty lines and the error report highlighted them, removed them again but no error report produced despite a 404 page not found. I hope i have communicated clearly the outcome.
many thanks for your support so far