Changes

Although this is an improvement on the original code, it would be helpful to provide yet more detail. The code, for example, does not provide any information about why email address was found to be incorrect. Adding this level of information involves the use of the exception error codes.

In addition to identifying the cause of a failure by finding the type of the exception, additional information can be obtained by inspecting the error code contained within the exception object. Error codes are currently available for the invalid user and user collision exceptions.