First off, let me thank you Vgers for such a FANTASTIC contribution. You have no idea how much your work means to everyone! It is much appreciated.
I've followed all the suggestions on this post and everything works well. I've included the Order_id change which allows Authorize.net to match the order numbers and that's helped a bunch.
However, life just isn't that simple huh? I have encountered 1 problem. When the customer's personal and credit card information is correct, everything works swimmingly. However, when the credit card is rejected, no error message is available to the customer. The user gets sent back to the payment page, using this URL:
Is there a way to parse this so the user can actually see the error message somewhere other than in the URL? This would mean so much....thank you in advance!