I'm going to have to quit OpenCart if I can't fix this!

I have been wrestling for more than a week, bouncing back and forth between my host server support team, OpenCart help and Authorize.Net, and no one can answer this for me. The issue (described below) prevents me from running CC transactions on my site. If I can't fix this, I can't run my business properly and will have to abandon OpenCart, which is drastic because I have invested so much time and some money into the configuration of OpenCart-based software. Every day I'm losing holiday season money because I can't turn the site up!

I recently installed OpenCart and am trying to get CC transactions to work with Authorize.Net (SIM). I have done this pre-OpenCart with Shop Site - a few hiccups occurred, related to it being a new Authorize.Net account, but it was doable.

Whenever I submit a transaction, I receive the following message immediately:

(13) The merchant login ID or password is invalid or the account is inactive.

From chatting with and talking to Authorize.Net and using their helps, there are three possible reasons for this message:
1) The account is inactive.
2) The wrong info is being sent.
3) OpenCart is sending to the wrong URL.

Following each path:
1) The account is clearly active. Authorize.Net agrees with this.

2) It's difficult to share this information because of the sensitivity. Even Authorize.Net Support does not want to know it. Generally, here is how I have configured the OpenCart Authorize.Net SIM module:

* Merchant ID field = my API Login ID.
* Transaction key = my Transaction key.
* MD5 Hash = my MD5 Hash.

I have re-genned my Transaction key and my MD5 Hash just in case, and used the new values. Same result.

Authorize.Net will not debug the transaction, but they referred me to http://developer.authorize.net/bin/developer/paramdump. There is a way to modify the Transaction Post URL in the script to display the transaction results, hence revealing the name/value pairs and verify whether the right info is being sent. I'm operating this at a user level and am uncertain where the script is and how to modify the script to do this. Ideas?

3) I find it hard to believe that OpenCart is sending to the wrong URL, but this is what Authorize.Net Support thinks is happening.

How can I find what URL it's sending to?

I understand that when in Test Mode, OpenCart is supposed to send to a different URL. I have tried running with Test Mode off and on, with both sides synced on Test vs. Live mode, but to no avail. (Authorize.Net recommended using a test credit card for a live transaction, but I can't even get that far).

Will someone out there please answer and get me unstuck so I can make progess?

I don't use authorize.net so cannot help you much, but the url is set in catalog/controller/payment/authorizenet_aim.php it looks like around line 89. there is also an authorizenet.sim.php file in there - not sure what the difference is since I've never used them.

It might be that authorize.net has changed something since 1.5x oc module was written (1.5x is about 2 years old), so you might want to look for an update on the payment gateway. http://www.opencart.com/index.php?route ... horize.net

If I were you, I would try switching other payment gateway first. Just to get your business going.