If your site is taking recurring donations this explains what happens when a transaction fails.

You can easily add PayPal as a payment option for your transactional systems within InfiPlex.

InfiPlex can integrate with the Authorize.net AIM (Advanced Integration Method) or CIM (Customer Information Manager) methods. Regardless of which option you choose, you will need to provide the System Merchant Application within InfiPlex your API Login ID and Transaction Key to enable merchant transactions with your Authorize.net account.

InfiPlex transactional apps have been designed to integrate with Authorize.net's Customer Information Manager (CIM). This allows users on your site to give recurring donations to your organization or save their credit card information for future transactions without storing any credit card informaiton on our servers. This document outlines the required set-up on your Authorize.net account to use the CIM with recurring donations.