[ic] Authorize.net

[iDevDirect.com]

Hi,

We have been successfully using authorize.net with IC for quite some time.
We recently sold a site that used our authorize.net account and are trying
to convert JUST that account to use the new owners authorize.net account.
We get the following error when trying to checkout (just on this site, our
other sites are fine).

(Payment process): There was an error accepting payment: Real-time charge
failed. Reason: Authorizenet error: The FDC Merchant ID or Terminal ID is
incorrect. Call Merchant Service Provider.. Please call in your order or try
again.

To my knowledge, we have never entered our MID and TID into IC or the
server.  I don't think the setup instructions called for it.

A) Do we need to adjust a variable now that we are using 2 authorize.net
accounts?

B) Is this an IC/Server setup issue or an authorize.net issue?

Sincerely,
Jim Webster