ORA-12514TNSlistener doesn't currently know of service requested in connect descriptr

[sonia.sardana]

When I connect in command prompt using username,password & Host String(tnsNames.ora). Its succeed as seen below.

C:\>sqlplus sonia/mypass@sonia - In this line First sonia is the userName & second Sonia is the host from the tnsnames.ora

SQL*Plus: Release 11.2.0.2.0 Production on Wed Jul 4 13:12:43 2012

Copyright (c) 1982, 2010, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Express Edition Release 11.2.0.2.0 - Production

But When I use the sqlPlus screen to connect to Oracle -
UserNAme - sonia
Password - mypass
HostString - sonia

I am getting ERROR - ORA-12514 TNSlistener does not currently know of service requested in connect descriptor.
I am not getting why I am not able to LOGIN FROM SQLPLUS SCREEN.

I searched on the net, But still No LUck.My database is also started which I find using the

 C:>sc query OracleServiceXE

tnsnames.ora (LOCATION - C:\oracle\product\10.2.0\client_1\network\admin\tnsnames.ora
)
# tnsnames.ora Network Configuration File: C:\oracle\product\10.2.0\client_1\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.

SONIA =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = sonia)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = SONIA)
)
)
[/code]


tnsNAmes.ora -C:\oraclexe\app\oracle\product\11.2.0\server\network\ADMIN

XE =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = sonia)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = XE)
    )
  )

EXTPROC_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
    )
    (CONNECT_DATA =
      (SID = PLSExtProc)
      (PRESENTATION = RO)
    )
  )

ORACLR_CONNECTION_DATA = 
  (DESCRIPTION = 
    (ADDRESS_LIST = 
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1)) 
    ) 
    (CONNECT_DATA = 
      (SID = CLRExtProc) 
      (PRESENTATION = RO) 
    ) 
  )

Listener.ora -C:\oraclexe\app\oracle\product\11.2.0\server\network\ADMIN

XE =
SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PLSExtProc)
      (ORACLE_HOME = C:\oraclexe\app\oracle\product\11.2.0\server)
      (PROGRAM = extproc)
    )
    (SID_DESC =
      (SID_NAME = CLRExtProc)
      (ORACLE_HOME = C:\oraclexe\app\oracle\product\11.2.0\server)
      (PROGRAM = extproc)
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
      (ADDRESS = (PROTOCOL = TCP)(HOST = sonia)(PORT = 1521))
    )
  )

DEFAULT_SERVICE_LISTENER = (XE)

I am still confused in that I have two tnsNames.ora in different locations.Is that OK?

[abhijit]

You have more than one ORACLE_HOME installation on the same machine. For some reason, this has always created issues for me in the past. My suggestion is to launch sqlplusw from the same directory as sqlplus and see if that resolves the issue.