Payment By Credit Card Has Stopped Working

For some reason the payment by credit card has stopped working sort of, I haven't changed anything but now when a customer tries to purchase they end up back at the shopping cart which says "The shopping cart is empty" not at the success page where an email is supposed to be sent to the customer with a survey. On checking the orders table the item has been added successfully and if I check the Paypal account the payment has been made successfully.

I just had a thought, I did do one change to the .hraccess file to rewrite all to https
RewriteEngine On
RewriteCond %{HTTPS} !=on
RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

Could this be the cause?

Are you starting at a domain that begins with www. and redirecting back to one without www. or vice versa?

Technically if you browse to a site with www.domain.com and then go to it with just domain.com, they have two different sessions and act as two different sites. The solution is to force traffic to always use one or the other. This can be done in the .htaccess as well.

For instance this would force to always have www in the domain:

RewriteCond %{HTTP_HOST} !^$
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteCond %{HTTPS}s ^on(s)|
RewriteRule ^ http%1://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L]

Then make sure your return page urls on the confirm.php page also include the "www." in the url for consistency. Also make sure the page urls on the confirm.php page include https:// now that you are using and forcing ssl.

I made the changes to the .htaccess file as you suggested and have managed to get the credit card to work although I was not able to add the https:// to the confim.php redirect, if I did it tried to redirect to: https://https:////www.championnutrition.net.nz/checkout_success.php so here is the redirect line that I have in the confirm.php:

$eCart1->redirStr = "//www.championnutrition.net.nz/checkout_success.php";

This works using a credit card but I have just tested it using PayPal and after making the payment you are redirected to:

https://www.championnutrition.net.nz/www.championnutrition.net.nz/checkout_success.php

and of course I get the following error:

Not Found

The requested URL /www.championnutrition.net.nz/checkout_success.php was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

Can you show me the context of that code? I think in that location it just has to be "checkout_success.php"

I have attached the confirm.php file.

Yes, since this is direct checkout and not express you can use just the page name.