Today I worked on setting up Authorize.net and osCommerce on one of the cell phone websites I have been working on. I ran into many problems with the default Authorize.net module. My final conclusion was that I was going to have to look for a better contribution.
During my initial tests using the default Authorize.net module, I was able to submit transactions to the authorize.net account which were processed in test mode, however the user was returned to the home page of our site, asking them to log in again or create an account. When we logged in again, thier shopping cart still had the product in there, and on the osCommerce side it looked like the actual order never took place.
I searched high and low for answers. Suprisingly there weren’t many on the web. I am currently testing this contribution ( Authorize Net AIM module (GPL) )