Trying to setup SIM - HTTP 500 error

[jp1]

So we currently use a locally hosted form through First Data.

I am trying to convert it to Authorize.Net  and inital tries are generating an HTTP 500 Internal server error when trying to pass my form data to the payment form.

I am passing my Login ID but the piece I think I am missing it how to formulate the Fingerprint to be able to display the authorize.net form. I see it discussed on page 28 of SIM developer guide but not sure how to pass that information to the web site.

[Lilith]

Fingerprint hash issues wouldn't cause an HTTP 500 error.

Are you able to provide the data you're attempting to send, with any Transaction Keys, CC#s, expiration dates, and CVV data censored?

And are you positive you're sending it via HTTP POST?