Ora-39126 Worker Unexpected Fatal Error In Kupw-worker.prepare-data-imp 71 Link

The error ORA-39126: Worker unexpected fatal error in KUPW$WORKER.PREPARE_DATA_IMP [71] is a generic "catch-all" internal error during an Oracle Data Pump import (impdp). It typically signifies an unhandled exception triggered by corrupted metadata, invalid system objects, or specific version incompatibilities. Common Root Causes

Root Cause: The target database lacked Oracle Spatial license or had MDSYS schema invalid objects. The error ORA-39126: Worker unexpected fatal error in

  1. Stop and review the import job; note current state from DBA_DATAPUMP_JOBS and DBA_DATAPUMP_SESSIONS.
  2. Examine the import log file and Oracle trace for the worker to identify exact exception/ORA- error chain.
  3. Verify dumpfile integrity: compare checksums, run file copy locally to DB server and test read.
  4. Check host resources and free space (including TEMP, FLASHBACK, and disk where dump resides).
  5. Re-run import with PARALLEL=1 and LOGGING=TRUE to reduce concurrency and produce clearer logs.
  6. If problem reproducible, run import on a test instance to isolate environmental issues.
  7. If suspect Data Pump bug, gather trace and contact Oracle Support with ADRCI package of traces.
impdp ... transform=lob_storage:no_change