Hi Gurus

version : oracle 10g (10.1.0.2.0) for 32 bit windows
when ever i am trying to use this utility expdp from command line it gives me this error'

c:\oracle\product\10.1.0\Db_1\bin> expdp system/password full=y

ORA -39002 : INVALID OPERATION
ORA- 39070 : UNABLE TO OPEN THE LOG FILE
ORA- 39087 : DIRECTORY NAME DATA_DUMP_DIR IS INVALID

PLEASE GUIDE ME do i have to set some more parameter in init file

thanks in advance
sonu