If the import fails, you may want to remove the designated ISOURCE database user and all the objects it owns before you can try again.
Procedure
- Start SQLPLUS /NOLOG from a shell where the ORACLE_SID and ORACLE_HOME variables are set correctly; at a command prompt type:
CONNECT SYS/CHANGE_ON_INSTALL AS SYSDBA
DROP USER ISOURCE CASCADE;
- Recreate the ISOURCE user.