Troubleshooting Exceptions: System.IdentityModel.Selectors.ServiceBusyException
A ServiceBusyException exception is thrown to indicate that the CardSpace service is busy processing other requests. CardSpace does not queue requests, and can service only one request at a time.
Determine whether another instance of CardSpace is running. If there is another instance running, end it by stopping the icardagt.exe process from Task Manager.
See Also
Tasks
How to: Use the Exception Assistant