When you see this error after impdp
Log into sqlplus as sys dba and type:
<SQL> ALTER SESSION SET EVENTS '30090 TRACE NAME CONTEXT FOREVER, LEVEL 32';
<SQL> EXEC DBMS_DST.UNLOAD_SECONDARY;
now you can try import in impdp.
When you see this error after impdp
Log into sqlplus as sys dba and type:
<SQL> ALTER SESSION SET EVENTS '30090 TRACE NAME CONTEXT FOREVER, LEVEL 32';
<SQL> EXEC DBMS_DST.UNLOAD_SECONDARY;
now you can try import in impdp.