Is this error happening at Runtime or when opening the project in Studio? Look in the appropriate log (turn on verbose logging if not on) and find the exception. Note what thread the exception happened on and then search upwards in the log for the previous line with that thread. That will help you to see what might be the issue.
I am getting this error while running the project from studio. I didn't even open application. I am using web adapter with monitorall. I didn't find any errors in the log file. Let me know what could be the reason.
Only first instance is running, next time onwards I am getting the error.