ODBCDatabase and WebApp

how i can find a crash on WebApp run perfect on the debug but when i use windows service for Standalone app it stop service with out any error

permissions are different, so you may run into an IOException or NilObjectException easily.

Maybe you log messages to see how far you come?

Are you running the service under the same user as the logged in user? By default, services run as System and have limited privileges.

same user

how i find the error log on windows 2012 server