When we click on add to cart from the main product listing page we get the correct URl with extra stuff on the end.  This is the only place that it happens.  It doesn't happen from the actual product listing page when clicking on 'add to cart'... only happens on the main 'Products' page.

Default.aspx?tabid=394&ctl=Cart&mid=1306?SkinSrc=/Portals/_default/Skins/iPadSoft/inner

This extra part of the URL is never displayed any place else on our website... only when clicking on 'add to cart' from the main products page.

DNN. 5.6.3

SC: 4.67.0

I'm talking about the main Store page.. the "Product Listing"  not the "product details".

Have you configured the BuyNow page name in the ProductDetails module settings?

Yes, but it works on the ProductDetails page.

Do you have a custom skin installed on your site?

If you mean are we using the default DNN skin, of course not.  Who does?   What would that have to do with it?