Symptoms
The following error message is seen when joining a conference using the Guest Attendee feature:
“Error: An internal error occurred while you were trying to join the conference. Please try again later. If the error persists, contact your conference host. Please click here to clear this error and login again.”

Resolution
While Guest Attendees don’t log on to Web Interface, Web Interface must be configured correctly so the Guest Attendee feature can locate the Citrix Farm. Ensure Web Interface can enumerate applications within the farm.