After 3 and a half days of reading through documentation and trial and error, I have come to a point where I am just stuck trying to make it so Community Users and/or normal Users can log into a salesforce org by using their FaceBook login credentials.

Has anybody had success with this where they can help me out?

I thought I had set up the Auth Provider correctly in Salesforce as well a Registration Handler class and also an App in Facebook, but when I try and use it for a fictitious Facebook account that should be tied to a Community User license in Salesforce I get an error along the lines of:

There was a problem with your authentication attempt. Please try again. If you continue to encounter problems, contact your administrator.

I notice in the URL it has at the end "AuthorizationError?ErrorCode=NO_ACCESS&ErrorDescription=User+was+a+portal+user".

Something tells me I am missing something really simple, but I am running out of things to try.

Any help would be greatly appreciated!