Hi, web development url
amykandco.com/dev2/
In System > Configuration > Main > Cart, I have set the option "After a product is added to the cart = Stay and display popup notice".
In Firefox and Safari, when I click on "Add to cart" the page stays put (seems to blink or refresh quickly). No pop up appears on product page. On the category page, the pop up is displayed correctly.
In IE9 (with or without compatibility view) and Google Chrome, when I click on "Add to cart" I am directed to a blank page from either/both the product pages and/or the category pages.
In all cases, when I go to the checkout page, the products have been added to the cart correctly.
I re-installed Hikashop Essentials 2.1.2 just to be sure and the problem persists.
Thanks for any help.