I installed authorize.net AIM onto my site. When I tried my American Express card, an error message came out "The credit card number starting with 3743 was not entered correctly, or we do not accept that kind of card. Please try again or use another credit card".
But when I keyed in the same card info on the virtual terminal on Authorize.net website, it went through.
The agent in Authorize.net said the problem lays in the Zencart. Does anybody know?
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