Oracle listener not running and won't start

Question

I am getting the following errors while from the lsnrctl status command:

C:\\Users\\pna105>lsnrctl stat

 LSNRCTL for 64-bit Windows: Version 11.         


        

Answer 1

In my Windows case the listener would not start, and 'lsnrctl start' would hang forever. The solution was to kill all processes of extproc. I suspect it had something funny to do with my vpn

Answer 2

1.Check the Environment variables (must be set for System and not for user):

ORACLE_HOME = C:\oraclexe\app\oracle\product\11.2.0\server
ORACLE_SID = XE

2.Check if you have the right definition in listener.ora

XE =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
      (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
    )
  )

DEFAULT_SERVICE_LISTENER = (XE)

3.Restart the service (Services > OracleServiceXE)

After that you may see a new service called OracleXETNSListenerXE.
There is already an old OracleXETNSListener.

I started both and then I was able to make a successful connection.

Edit:

If everything is running but you still can't connect, check if there is no error: ORA-12557: TNS:protocol adapter not loadable.

To correct the error go back to the Environment variables and this time edit the one called: Path. Be sure that C:\oraclexe\app\oracle\product\11.2.0\server\bin is somewhere at the beginning, definitely before any other path pointing to a different version of the Oracle DB.

Answer 3

I encountered the same problem and reason being: Mine is a personal windows PC. And i have modified the computer name and the same did not reflect in listener.ora. Updating ORACLE_HOME\network\ADMIN\listener.ora with updated host name fixed the issue.

Answer 4

Problem

The listener service is stopped in services.msc.

Cause

User password was changed.

Solution

• Open services.msc.
• Right-click the specific listener service.
• Click Properties.
• Click the Logon tab.
• Change the password.
• Click OK.
• Start the service.

Answer 5

Same happened to me after I changed computer name. To fix that, just locate listener.ora file and replace old computer name with the new one

Answer 6

I solved it by updating listener.ora file inside oracle directory oraclexe\app\oracle\product\11.2.0\server\network\ADMIN.

Why did it happen to me was because I changed my system name but inside listener.ora there was old name for HOST.

This might be one of the reasons... for those who still face such issue might think of this possibility as well.