Ora-39126 Worker Unexpected Fatal Error In Kupw-worker.prepare-data-imp 71 May 2026

impdp ... LOGTIME=ALL TRACE=480300

ORA-39126: Worker unexpected fatal error in KUPW$WORKER.PREPARE_DATA_IMP [71]

The full error message usually appears as:

| Cause | Description | |-------|-------------| | | File transfer errors (binary vs. ASCII), incomplete dump, or storage corruption | | Character set mismatch | Source and target databases have incompatible character sets, especially with NCLOB/NVARCHAR2 | | Invalid table definition | Table on target has columns that conflict with dump file (data type, length, partition differences) | | Object already exists | Table exists but with constraints/triggers that block Data Pump transformation | | Oracle Bug | Known issues in specific versions (especially 11.2, 12.1, 18c, and early 19c) | | Insufficient privileges | Worker cannot perform a required operation due to missing grants |