How To Change Instance name in Oracle

Hello,
Here I show you how to change instance name in oracle database, let's check instance name:

SQL> show parameter instance_name;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
instance_name                        string      orcl

In Linux:
We want to change instance name which is orcl to test.
if we are using spfile we need to do

SQL> show parameter spfile

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
spfile                               string      +DISKS/orcl/spfileorcl.ora

SQL> alter system set instance_name=test scope=spfile;
System altered.
SQL> shutdown immediate;
........
SQL> startup;
........
SQL> show parameter instance_name
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
instance_name                        string      TEST

If we are using pfile, then change instance_name parameter in that and restart database, if there is not instane_name parameter then add.
Note: It's strongly recommended that using spfile
In Windows:
We need to create service with ORADIM

set ORACLE_SID=TEST
c:\app\oracle\product\11.2.0\db_1\bin\oradim -new -sid TEST -SRVC OracleServiceTEST 
-STARTMODE auto -SRVCSTART system -PFILE
c:\app\oracle\product\11.2.0\db_1\database\INITTEST.ORA

after that delete old instance

c:\app\oracle\product\11.2.0\db_1\bin\oradim -DELETE -SID orcl

Until you did not delete your old instance you always got error so first delete your old instance and then check your instance name.
good by :)