In the first versions of Prestashop 1.5.* there is a bug which is reproduced in old versions for all browsers as well as in all Internet Explorer versions. This bug does not allow to save cookies when adding a product to the cart if the Block Cart module is enabled, thus your shopping cart remains empty. To fix this you need to modify the js-file /modules/blockcart/ajax-cart.js:
Comment out the following condition in the method аjаxCаrt.add(): //if($('#cart_block #cart_block_list').hasClass('collapsed'))
Place an аjаx-request in the method аjаxCаrt.expand() before slideUp is invoked.
Then set the same аjаx request for a synchronous execution, i.e.set the async option as false, instead of true.
After that clear your browser cookies.
Posted in: Prestashop