This specific error is frequently linked to metadata inconsistencies or environment-specific bugs:

Attempting to import system-related schemas (like SYSMAN ) across different Oracle versions (e.g., 11g to 12c) often triggers internal preparation errors. Troubleshooting and Resolution Steps 1. Rebuild Data Pump Metadata

After running this, recompile any remaining invalid objects using the utlrp.sql script. 2. Exclude Statistics

The error is an internal exception within the Oracle Data Pump (impdp) utility. It occurs when a worker process encounters an unhandled state while preparing data for import, often leading to a premature job termination. Common Causes

If the issue is caused by a corrupt Data Pump catalog, you can re-register the components by running the dpload.sql script as a SYSDBA user:

Stale or corrupt optimizer statistics in the source dump file can cause the worker to crash during the preparation phase.