ORA-31463: logfile location string is an empty directory
Cause: The directory specification for logfile location for the change source, is an empty directory
Action: 1. Make sure it is the correct location of the logfiles. If it is, make sure the directory contains logfiles. OR 2. perform ALTER CHANGE SOURCE and change the logfile_location to be an existing directory that contains the logfiles
https://support.oracle.com/
http://www.oracle.com/