Exception Message The caller was not authenticated by the service

Problem Events:
 Display Error in Control Panel: Error: An unknown exception has occurred. Please check exception logs for more detail
Exception Message in Panel :  The caller was not authenticated by the service.
 
Solution:
These error appears in the control panel if authentication fails for the server instance that is added in the HC Panel. You can verify and update the user credentials by accessing control panel at admin level > Server Manager > Select the Server > click Edit button.
 
If problem persists then please contact HC Support Team