Catalook: Issue on page where there is the CAT_Cart module

Hello,

• I have a Module Specific rule for the CAT_Cart module: I simply disabled URL Rewriting. However, I experience that
• when I have one item in the cart,
• and press Checkout,
• it does not goes further to the second cartpageno. The URL remains like this: domain.com/Default.aspx?tabid=145 - and there is no cartpageno parameter in the URL - I guess that's why is this issue.

So, however the URL rewrite is disabled on this page I think the FUP causes the issue.

Do you have any suggestion how we could find out if the FUP causes the issue?

domain: radioamatorwebshop.eu

Page which has the CAT_Cart module: in the upper menu with title: "Kosár & Fizetés".