Oracle 11g Ora-12514:tns: The listener does not currently recognize the requested service in the connection descriptor

1. Locate the Listener.ora listening file, in the exact location: D:\app\Administrator\product\11.2.0\dbhome_1\NETWORK\ADMIN\listener.ora

2. Found in the Lisener.ora file

(Sid_desc =
(Sid_name = Clrextproc)
(Oracle_home = D:\app\Administrator\product\11.2.0\dbhome_1)
(program = Extproc)
(Envs = "Extproc_dlls=only:d:\app\administrator\product\11.2.0\dbhome_1\bin\oraclr11.dll")
)

Copy the following section and modify it appropriately. (The Scarlet Letter part is your SID, where Global_dbname is the global database name and can differ from SID)

(Sid_desc =
(Global_dbname = ORAC11)
(Oracle_home = D:\app\Administrator\product\11.2.0\dbhome_1)
(Sid_name = ORAC11)
)

3. Save the Listener.ora file, close and restart the listener.

Lsnrctl Stop//Off

Lsnrctl Start//Startup

4. At this time, with the normal user to connect the double appears new error.

Ora-27101:shared Memory Realm does not exist5. Start Open Directory: D:\app\Administrator\admin\orac11\pfile, you will find a file in it: init.ora.1052011103553, which is the startup file backed up by Oracle's last successful boot.  6. Sqlplus/nolog, create SPFile from pfile= ' D:\app\Administrator\admin\orac11\pfile\init.ora.1052011103553 ' startup Start the database. 7. Everything is back to normal.

Oracle 11g Ora-12514:tns: The listener does not currently recognize the requested service in the connection descriptor