accept accepted account authorize cart client discover enters error happens net purchase return shopping show warning

I have a client that does not accept discover card through their Authorize.net account. What happens if someone enters a discover card on the shopping cart through e-junkie and then it's not accepted through authorize.net? Do they get a warning that the card won't work or does the purchase go through?

That's a question for Authorize.Net. We'll simply show the error they return.