*Startup Error: Root element is missing.

************** Exception Text **************
System.Configuration.ConfigurationErrorsException: Configuration system failed to initialize ---> System.Configuration.ConfigurationErrorsException: Root element is missing. (C:\Users\...\AppData\Local\OfficeDoxs_Software,_Inc.\Booking_Agent.exe_Url_hdhlwtryjzaxoc5a4pjk3tcclgyqnalf\1.0.0.0\user.config)

Resolution:

Delete directory C:\Users\...\AppData\Local\OfficeDoxs_Software,_Inc.\Booking_Agent.exe_Url_hdhlwtryjzaxoc5a4pjk3tcclgyqnalf\.