Authorize.net error when trying to relay response to page in protected folder?

[longlam]

Hello,

 

I am trying to set up a relay response using the SIM mode.

 

I get an authorization error and I am guessing that it is because the response page that I am redirecting to is in a protected folder that requires a username/password to get into it, ie the admin area. Can you please confirm if this is the reason for the error and if it is how can I work around it?

 

Thanks.