HI- Today I contacted authorize.net and they gave me a "dump url" that I was supposed to look at to see what information was being passed. It was empty, so they said no parameters were being passed.

I did some research on the forums, and I've done this:

1. Leave it in test mode on zen cart but changed it to production mode on Authorize.net. result: although I've placed several orders, there are no unsettled transactions to look at:

2. Another problem is the AMEX and Discover numbers given in test mode are being refused. It was suggested to change the transaction key. I've done this, no change.

I'm on 1.3.9g. here are my settings:
Enable Authorize.net (AIM) Module
True

Login ID
**********

Transaction Key
****************

MD5 Hash
****************

Transaction Mode
Test

Authorization Type
Authorize+Capture

Enable Database Storage
True

Customer Notifications
False

Merchant Notifications
False

Request CVV Number
True

Sort order of display.
0

Payment Zone
--none--

Set Completed Order Status
Processing [2]

Set Refunded Order Status
Pending [1]

Debug Mode
Off

Does anyone have any suggestions? Thanks!