I am working on converting from Authorize.net to First Data (FD) and am running into issues processing payments. There is something I just don't have right.

I have followed all the directions from First Data regarding the changes necessary to the authorizenet.php file. I am able to enter all my credit card info, it's once I click "Pay Now" that I have trouble.

In the Receipt Page of the FD Payment Pages, if I have "http://www.website.com/index.php?main_page=checkout_process entered in the Receipt URL field, when I click on Pay Now I receive a message from Zen-Cart that says "There was an error processing your order ....." The credit card is successfully charged but the order never shows up in the cart.

If I have "http://www.website.com/index.php?main_page=checkout_sccess" in the Receipt URL field when I click on Pay Now I receive a message from Zen-Cart that says "Whoops! Your session has expired." Again the card is charged but the order is never recorded.

Are there any logs that can help troubleshoot this? There is nothing in the /cache directory.

I tried contacting First Data but after a while the representative told me it was on the cart end and there was nothing they could do.

Help?