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

Apply the latest or upgrade to a stable version:

: Ensure the default temporary tablespace is correctly assigned and has active tempfiles. Apply the latest or upgrade to a stable

If you are unable to resolve the issue using the above steps, you may want to engage Oracle Support or a certified Oracle professional for further assistance. They can help you: Apply the latest or upgrade to a stable

ORA-39126: Worker unexpected fatal error in KUPW$WORKER.PREPARE_DATA_IMP [71] Apply the latest or upgrade to a stable

If the source uses SecureFiles LOBs and the target uses BasicFiles (or vice versa), or if the target tablespace lacks space for LOB segments, the PREPARE-DATA phase may crash.

Data Pump remains one of the most powerful tools in the Oracle DBA’s arsenal. With patience and the right diagnostic approach, even a "fatal error" becomes a solvable puzzle.