"I'm having the same problem" is too generic a statement ... esp since the previous poster was quite vague in what their full situation is.
So, let's start from the top.
- What version of Zen Cart are you using?
- What addons/contributions do you have installed?
- Who is your hosting company?
- What is your URL?
- Which Authorize.net module are you using?
- What exactly have you done to set it up?
- What exactly are you doing when the problem occurs?
- What exactly is the problem you're experiencing? including exact error messages.
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