Cart Cookie
Thanks to tostrinj (Paul) and spectreman (Eric) for pointing out this bug.
After the order has been successfully placed, the cookie was not being deleted. Hence, even though the customer went through the checkout process, it still showed items in the customer's shopping cart.
Only file containing the installation instructions has changed.
Make the following change in catalog/checkout_success.php
Immediately following the line (Line # 13):
require('includes/application_top.php');
Place the following lines:
$cookie_path = HTTP_COOKIE_PATH;
$cookie_expiration_time = time() - (MAX_LIFE_OF_CART_COOKIE * 24 * 60 * 60);
setcookie("cart", false, $cookie_expiration_time, $cookie_path, $cookie_domain);
http://addons.oscommerce.com/info/5390