When you access a non-existent page Openсart redirects to the "Page not found" but the response of the server 200 (everything is OK), not 404 (page not found).
This is true for the Catalog, Manufacturers, Categories, and Information pages for all Opencart 1.5.x versions.
(this problem has been solved in Opencart 18.104.22.168 and 2.x)
For example - link such as site.com/index.php?route=product/product&product_id=404040404040
fixes this problem, after apply server response for non-existent page will be 404 (page not found)
✯ Compatible with Opencart 1.5.0.x - 22.214.171.124
✯ No files are replaced
✯ Don't creates additional tables or fields in database
✯ Required VQMOD
Just copy xml-file into vqmod/xml directory
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