Errors ORA-31693 and ORA-29913 thrown during import

Yesterday when importing some test data from production to test, I encountered the following error during import:

. . imported "< schema name >"."< table name > ":"< partition name >" 77.08 KB 0 rows
ORA-31693: Table data object "< schema name >"."< table name > ":"< partition name >" failed to load/unload and is being skipped due to error:
ORA-29913: error in executing ODCIEXTTABLEOPEN callout
. . imported "< schema name >"."< table name > ":"< partition name >" 25.69 KB 0 rows

The preceeding export executed successfully, without any errors or warnings. I used multiple threads, and the result was 7 dump files.

I first tried reimporting the table, which in many similar cases actually work. This time, it didn't; the same error was thrown.

The solution was to remove the parallel directive from the import parameter file and reimport only the missing table:

USERID='/ AS SYSDBA'
DIRECTORY=DPUMP
DUMPFILE=EXDP_SCHEMA_EXPORT_201311181340_%U.DMP
LOGFILE=IMPDP_missing_tables.log
PARALLEL=1
TRANSFORM=OID:N
TABLE_EXISTS_ACTION=REPLACE
REMAP_SCHEMA=< schema_name >:
TABLES=< schema_name >.< table_name >

. . imported "< schema name >"."< table name > ":"< partition name >" 77.08 KB 0 rows
. . imported "< schema name >"."< table name > ":"< partition name >" 1.205 GB 6758593 rows
. . imported "< schema name >"."< table name > ":"< partition name >" 25.69 KB 0 rows