ORA-12505:
	TNS:listener does not currently know of SID given in connect descriptor
Cause: 	The listener received a request to establish a connection to a database or other service. The connect descriptor received by the listener specified a SID for an instance (usually a database instance) that either has not yet dynamically registered with the listener or has not been statically configured for the listener. This may be a temporary condition such as after the listener has started, but before the database instance has registered with the listener.
Action: 	

- Wait a moment and try to connect a second time.

- Check which instances are currently known by the listener by executing: lsnrctl services <listener name>

- Check that the SID parameter in the connect descriptor specifies an instance known by the listener.

- Check for an event in the listener.log file.

LISTENER.ORA

SID_LIST_LISTENER =
	(SID_LIST =
		(SID_DESC =
			(SID_NAME = PLSExtProc)
			(ORACLE_HOME = C:\oracle\product\10.2.0\db_1)
			(PROGRAM = extproc)
		)
	)

LISTENER =
	(DESCRIPTION_LIST =
		 (DESCRIPTION =
	 		 (ADDRESS = (PROTOCOL = TCP)(HOST = teamcenter07)(PORT = 1521))
			 (ADDRESS = (PROTOCOL = IPC)(KEY = extproc))
		 )
	)

TNSNAMES.ORA

ORCL =
	(DESCRIPTION =
		(ADDRESS_LIST =
			(ADDRESS = (PROTOCOL = TCP)(HOST = teamcenter07)(PORT = 1521))
		)
		(CONNECT_DATA =
			(SERVICE_NAME = orcl)
		)
	)

lsnrctl services <listener name>

Here are the results of the lsnrctl status

LSNRCTL for 32-bit Windows: Version 10.2.0.1.0 - Production on 23-JUN-2009 09:44
:54

Copyright (c) 1991, 2005, Oracle. All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=teamcenter07)(PORT=1521)
))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for 32-bit Windows: Version 10.2.0.1.0 - Produ
ction
Start Date 23-JUN-2009 09:42:09
Uptime 0 days 0 hr. 2 min. 45 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File C:\oracle\product\10.2.0\db_1\network\admin\listener.o
ra
Listener Log File C:\oracle\product\10.2.0\db_1\network\log\listener.log

Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=teamcenter07.tisuk.thales)(PORT=1521
)))
Services Summary...
Service "PLSExtProc" has 1 instance(s).
Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "orcl" has 1 instance(s).
Instance "orcl", status READY, has 1 handler(s) for this service...
Service "orclXDB" has 1 instance(s).
Instance "orcl", status READY, has 1 handler(s) for this service...
Service "orcl_XPT" has 1 instance(s).
Instance "orcl", status READY, has 1 handler(s) for this service...
The command completed successfully


And the results of lsnrctl service

LSNRCTL for 32-bit Windows: Version 10.2.0.1.0 - Production on 23-JUN-2009 09:46
:12

Copyright (c) 1991, 2005, Oracle. All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=teamcenter07)(PORT=1521)
))
Services Summary...
Service "PLSExtProc" has 1 instance(s).
Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:0 refused:0
LOCAL SERVER
Service "orcl" has 1 instance(s).
Instance "orcl", status READY, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:2 refused:0 state:ready
LOCAL SERVER
Service "orclXDB" has 1 instance(s).
Instance "orcl", status READY, has 1 handler(s) for this service...
Handler(s):
"D000" established:0 refused:0 current:0 max:1002 state:ready
DISPATCHER <machine: TEAMCENTER07, pid: 1736>
(ADDRESS=(PROTOCOL=tcp)(HOST=teamcenter07.tisuk.thales)(PORT=1033))
Service "orcl_XPT" has 1 instance(s).
Instance "orcl", status READY, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:2 refused:0 state:ready
LOCAL SERVER
The command completed successfully 

ORCL =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = teamcenter07)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = orcl)
)
)