My users can't seem to integrate Facebook, Twitter, or G+ via the 'External Accounts' link in XenForo. They get the following errors:
For FB: App Not Setup: This app is still in development mode, and you don't have access to it. Switch to a registered test user or ask an app admin for permissions.
For Twitter: An unexpected error occurred. Please try again later.
For Google: 401. That’s an error. Error: invalid_client no application name
I'm sure I must not have something set up correctly - but what?