thanks julian
I have tried this way but problem is still same
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C:\oracle\product\10.1.0\Db_1\BIN>sqlplus / as sysdba

SQL*Plus: Release 10.1.0.2.0 - Production on Tue Jun 15 14:40:04 2004

Copyright (c) 1982, 2004, Oracle. All rights reserved.


Connected to:
Oracle Database 10g Enterprise Edition Release 10.1.0.2.0 - Production
With the Partitioning, OLAP and Data Mining options

SYS AS SYSDBA at master>create directory data_pumo_dir as 'C:\oracle';

Directory created.

SYS AS SYSDBA at master>commit;

Commit complete.

SYS AS SYSDBA at master>disc
Disconnected from Oracle Database 10g Enterprise Edition Release 10.1.0.2.0 - Pr
oduction
With the Partitioning, OLAP and Data Mining options
at >exit

C:\oracle\product\10.1.0\Db_1\BIN>expdp system/oracle10g directory=data_pump_dir
dumpfile=exp%U.dat full=y

Export: Release 10.1.0.2.0 - Production on Tuesday, 15 June, 2004 14:41

Copyright (c) 2003, Oracle. All rights reserved.

Connected to: Oracle Database 10g Enterprise Edition Release 10.1.0.2.0 - Produc
tion
With the Partitioning, OLAP and Data Mining options
ORA-39002: invalid operation
ORA-39070: Unable to open the log file.
ORA-39087: directory name DATA_PUMP_DIR is invalid
C:\oracle\product\10.1.0\Db_1\BIN>
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please guide me

Sonu