ORA-39141: dump file "[string]" is a duplicate of dump file "[string]"
Cause: When a dump file set consists of multiple files, all files in the set must be specified for an import operation. One of the files provided to import was found to be a duplicate of another dump file in the set. This can occur if the files in the dump set were copied or renamed using operating system utilities and the same dump file was inadvertently copied more than once with different destination names.
Action: Remove the dump file indicated in the message and retry the import operation providing only the complete set of dump files created by a specific export job.