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When finished, click "Update Settings" to save the details. You have successfully installed and configured Authorize.net!
Potential Issues
Q: When in sandbox mode, I get an error that says "Payment could not be authorized for the selected payment account. Please select a different account or try again." during checkout.
A: Please use the American Express test card from https://developer.authorize.net/hello_world/testing_guide.html Some of the other cards do not pass the regular expression card type checks as a real card would.