A base exception class is defined as the super class for all external exceptions. Specific exceptions always inherit from the base exception. To enable you, the Object API developer, to write a standard exception handler, all external exceptions have an error code and a single error message. Furthermore, the exception may contain another exception as the cause. See the Developer Guide: Device Client Error Reference for detailed information.
You can use the GetLocalizedMessage (string localeName) method to retrieve an error message for a specified locale.
See the Object API Applications section of the Developer Guide: Device Client Error Reference for information about possible error codes and the corresponding error messages.