I get such error when using data pump to export a 10.2.0.4 database, Here is the error message,

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D:\oracle\ORA1020>bin\expdp ‘/ as sysdba’ directory=mydir dumpfile=syn01a_full_e
xpdp_090810_1.dmp logfile=syn01a_full_expdp_090810_1.log

Export: Release 10.2.0.4.0 – Production on Monday, 10 August, 2009 1:41:30

Copyright (c) 2003, 2007, oracle.  All rights reserved.

Connected to: oracle Database 10g Enterprise Edition Release 10.2.0.4.0 – Produc
tion
With the OLAP, Data Mining and Real Application Testing options
Starting “SYS”.”SYS_EXPORT_SCHEMA_01″:  ‘/******** AS SYSDBA’ directory=mydir du
mpfile=syn01a_full_expdp_090810_1.dmp logfile=syn01a_full_expdp_090810_1.log
Estimate in progress using BLOCKS method…
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
Total estimation using BLOCKS method: 0 KB
Processing object type SCHEMA_EXPORT/ROLE_GRANT
orA-39127: unexpected error from call to export_string :=SYS.DBMS_AW_EXP.schema_
info_exp(‘SYS’,1,1,’09.02.00.00.00′,newblock)
orA-37002: oracle OLAP failed to initialize. Please contact oracle OLAP technica
l support.
orA-33262: Analytic workspace EXPRESS does not exist.
orA-06512: at “SYS.DBMS_AW”, line 93
orA-06512: at “SYS.DBMS_AW”, line 122
orA-06512: at “SYS.DBMS_AW_EXP”, line 476
orA-06512: at line 1
orA-06512: at “SYS.DBMS_METADATA”, line 5419
Master table “SYS”.”SYS_EXPORT_SCHEMA_01″ successfully loaded/unloaded
******************************************************************************
Dump file set for SYS.SYS_EXPORT_SCHEMA_01 is:
  J:\ORACLE\ADMIN\SYN01A\EXPORTS\SYN01A_FULL_EXPDP_090810_1.DMP
Job “SYS”.”SYS_EXPORT_SCHEMA_01″ completed with 1 error(s) at 01:41:41
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After searching on metalink, i get something very useful, it says
the root cause may be that, oracle OLAP is not installed or not configured properly. This can also happen after database upgrades.

I remeber this database was upgraded from 9.2.0.8 to 10.2.0.4 some weeks before,
and after I apply the solution which is provided by Metalink to my database, the problem disappears. GREAT !

document id: 731614.1
Subject: EXP-00008: oracle OLAP failed to initialize Error During Database Export
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To implement the solution, please execute the following steps:

To avoid this problem, perform relational exports excluding OLAP’s Analytic Workspaces.
1) You might want to make a full backup of your database before attempting the following steps.
2) Remove workspace package from export:

a. Connect sys/password as sysdba
b. create table sys.exppkgact$_backup as select * from sys.exppkgact$;
(Backup package before deleting it)
c. delete from sys.exppkgact$ where package = ‘DBMS_AW_EXP’ and
schema= ‘SYS’;
d. commit;
3) Run the FULL export.

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