The following errors have occurred.
(13) The merchant login ID or password is invalid or the account is inactive.

So which is it? Do I have an invalid ID, password, or is the account inactive?

Bad error messages are the suck. There's no reason the system shouldn't know which of these three cases is the reason for failing.

Followup: The context of this error is I'm attempting to connect to authorize.net's gateway to process some credit card transactions (unfortunately I'm stuck doing these boring, menial webmaster-esque tasks every once in a while). Obviously, I didn't want to run through an actual credit card transaction, so I was using (what I thought) was their test gateway which would work with *my* user credentials (https://test.authorize.net). However, what I'm supposed to do is use their real gateway (https://secure.authorize.net) and send in a stringified boolean x_test_request. So that error message was actually telling me: "Hey, the API login you're using is actually a "live" account ID (as opposed to a "test" account ID), so please use https://secure.authorize.net. Unless you have a test account, in which case you've input the wrong login id, the wrong password, or your test account is inactive.

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