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Unable to connect

I am unable to connect using Direct option. Can you please guide ?
ORA-12541: TNS:no listener

Items Checked

TNS_ADMIN environment variable is not defined

ORACLE_HOME environment variable is defined as "C:\Deshdb\Ora19C"

"C:\Deshdb\Ora19C\Network\Admin\sqlnet.ora" was located

NAMES.DIRECTORY_PATH specifies EZCONNECT in the sqlnet.ora file

Steps to Take
Verify that the correct port is specified
Verify that the listener is running and that it is properly configured
Try to ping using the Ping button on the toolbar
Try to TNSPing (DESCRIPTION=(ADDRESS=(PORT=1521)(HOST= using the TNS Ping button on the toolbar

Morning Sanjay.

The error says that there isn't a listener running on the server and/or port you specified in the direct options.

If you can login to the server ( and execute the lsnrctl status command, it will tell you if there is a listener running and the port it is on.

On Windows, you might need to start the listener service using control panel-> services as, if I remember, the listener is not started automatically by default.


Norm. [TeamT]

Happy New Year Norm and thanks for your reply.
I tried to start listener service but I could not see any option on control panel-> services except ....
1)Oraclejob scheduler
4)OracleService (for my database)
5)OracleVssWriter (for my database)

Also, I could not login to the server to execute lsnrctl status
How to resolve this ?

Hi Sanjay,

The listener service name is OracleHOMENAMETNSListener -- so you need to be looking under whatever name you gave the Oracle Home at installation time. If the name was dbhome1 the look forOracledbhome1T|nSListener.

Yours could be OracleOraDB19Home1TNSListener.

From 12c it should be started at boot time of the server. But can obviously be configured otherwise, and manually shut down/started.

To login to the server you need to get access from the sys admins, then just login using the Windows RemoteDesktop application and the credentials you've been given.

Obviously, if you have to start/stop the listener, you'll need to gain access to the oracle user account. looks like a "local" IP address, is that your own computer or is that the database server?

Norm. [Team]

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