Authorize.net provides payment processing and payment management services to help businesses accept credit card and e-check payments online
In the E-Commerce Configuration proceed to Settings > Webstore. Scroll down to “Credit Card Gateway” and select Authorize.net from the dropdown. It will show you the fields to fill in:
Authorize.net Login ID
Authorize.net Public Client Key
Authorize.net Transaction Key
Now, proceed to your Authorize.net account home page. On the left-hand menu under Account, select Settings.
Under Security Settings > General Security Settings there are two links that you need to visit to retrieve information:
Manage Public Client Key (this page shows you the Authorize.net Public Client Key which is referred to as the “Client Key”
API Credentials & Keys (this page shows you the Authorize.net Login ID as API Login ID. The Authorize.net Transaction Key is only shown when you create it, so you can create a new one at the bottom of the page. Be sure to create a Transaction Key and NOT a Signature Key.)
Note: Creating a new transaction key will invalidate the current transaction key if any.
Once you harvest the credentials from the above Step 3 and enter them into the E-Commerce Configuration you should be good to go!