ORA-00824:cannot set sga_target due to existing internal setting --SOLUTION

ORA-00824:cannot set sga_target due to existing internal setting --SOLUTION[@more@]C:Documents and SettingsAdministrator>sqlplus / as sysdba
SQL*Plus: Release 10.2.0.1.0 - Production on Thu Oct 14 21:46:55 2010
Copyright (c) 1982, 2005, Oracle. All rights reserved.

Connected to an idle instance.

SQL> startup
ORA-00824: cannot set sga_target due to existing internal settings, see alert log for more information

#to solve this problem#

1-create pfile from your spfiel
SQL> create pfile from spfile='E:oracleproduct10.2.0db_1dbsSPFILEORCL.ORA';
File created.

SQL> exit
Disconnected

2- open the pfile and make this changes and save it

delete this parameters

---

orcl.__java_pool_size=4194304
orcl.__large_pool_size=4194304
orcl.__shared_pool_size=96468992
orcl.__streams_pool_size=0
*.db_block_buffers=512

change value of this parameters to zero

---

*.sga_max_size=471859200 ----------&gt *.sga_max_size=0
*.sga_target=38294344 -----------&gt *.sga_target=0

change value of this parameters

---

*.db_cache_size=272629760 ----------&gt *.db_cache_size=272629760
.java_pool_size= 0 ----------&gt.java_pool_size=104857600
.large_pool_size=0 ----------&gt.large_pool_size=104857600
.shared_pool_size=0 ----------&gt.shared_pool_size=104857600

3-startup the database from pfile

SQL> startup pfile='E:oracleproduct10.2.0db_1databaseinitorcl.ora';
ORACLE instance started.

Total System Global Area 306184192 bytes
Fixed Size 1248696 bytes
Variable Size 205521480 bytes
Database Buffers 96468992 bytes
Redo Buffers 2945024 bytes
Database mounted.
Database opened.

4-create spfile from pfile and restart your database
SQL> create spfile from pfile;

File created.

SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.

Total System Global Area 306184192 bytes
Fixed Size 1248696 bytes
Variable Size 205521480 bytes
Database Buffers 96468992 bytes
Redo Buffers 2945024 bytes
Database mounted.
Database opened.