I am building a Magento module that needs to set risk scores based upon certain responses from the Authorize.net payment gateway. In case you need to run some tests of your own, there is an easy way to get specific responses back so you can test them easily.
First think you’ll need to know is a list of all the possible responses and response reasons. You can get that here: http://developer.authorize.net/guides/AIM/
To get back a specific response, use the test VISA number of: 4222222222222. Find the response code you want to test, and set the dollar amount to the code. So if you used the test credit card number, and made a transaction for $6, you would get back a response of “The credit card number is invalid.”.
You can do that programmatically, or if you are using Magento or some other shopping cart application, you can easily make a $6 product and not charge for shipping or tax.