The exact steps to configuring your credit card processing gateway with your UltraCart account will differ from gateway to gateway.
Integrated Gateways
Supported Transaction gateway services
UltraCart is integrated with over 100 payment processing services.
Please review the integrated gateways here: Credit Card Processing Transaction Gateway Integration list
However, the basic process is fairly simple: You'll gather your credit card gateway API credentials from the gateway and then configure the gateway credentials within the Transaction Gateways tab in the payments configuration page, and alternatively within the Rotating Transaction Gateways tab, if you are going to have more than one credit card processing gateway configured with your UltraCart account.
Transaction Gateways
Single Gateway integrations are configured in the "Transaction Gateways" tab in the payments configuration page:
Rotating Gatways
Then your configure the AVS (Address Verification Service) & CVV (Card verification value) rules within your gateways website.
Payment Gateway AVS and CVV rules
The AVS rules provide authorization validation against the supplied billing address. It's recommended that review the configuration options in the gateway and configure the AVS rules to validate against the numeric portion of the billing address and the 5 digit zip code.
The configuration of the CVV rules will depend on your particular needs. If you are selling items that are a subscription or continuity purchase items, then you'll need to adjust the CVV rules to turn off rules for declining the the order if the CVV number is "missing" or "unavailable", but you can and should leave enabled the rule for declining one CVV mismatch, as UltraCart will ask for the CVV number during the customers' initial checkout (unless you choose to turn that off (see the "Collect card verification number" checkbox seeing here)
And then once you have configured the transaction gateway rules, you're ready to test the new gateway configuration with a live test order to verify that everything it functioning properly. After your live test order has processed successfully, you can place additional test orders using our test credit card configuration which will allow you to place test orders without actually communicating to the gateway (thereby eliminating transactions fee from accruing.)