Resolving the “ORA-12514: No TNS Listener” error with Oracle XE

I faced this particularly nagging error with a personal install of Oracle XE (Oracle Database 10g Express Edition) on my Windows XP laptop:

ORA-12514:No TNS Listener

The SQL Command prompt that came with Oracle XE would work but none of the other tools like Toad, SQL Plus or even the Oracle XE Database Homepage which would open in a browser window would work.

The final resolution after a lot of research seemed to be painfully simple:

  1. Run the LSNRCTL.EXE program from the BIN directory of your Oracle XE install (default: C:\oraclexe\app\oracle\product\10.2.0\server\BIN). You should even be able to run it from any command prompt since the BIN directory is generally added to your PATH environment variable by default.
  2. At the LSNRCTL> command prompt, issue the STOP command. It should say:

    The command completed successfully

  3. Now, at the LSNRCTL> prompt, issue the START command. It should return:

    Starting tnslsnr: please wait…

    TNSLSNR for 32-bit Windows: Version – Production
    System parameter file is C:\oraclexe\app\oracle\product\10.2.0\server\NETWORK\AD
    Log messages written to C:\oraclexe\app\oracle\product\10.2.0\server\network\log
    Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=hostname)(PORT=port)))

    Alias                     LISTENER
    Version                   TNSLSNR for 32-bit Windows: Version – Produ
    Start Date                14-MAY-2009 01:24:49
    Uptime                    0 days 0 hr. 0 min. 5 sec
    Trace Level               off
    Security                  ON: Local OS Authentication
    SNMP                      OFF
    Default Service           XE
    Listener Parameter File   C:\oraclexe\app\oracle\product\10.2.0\server\NETWORK\ADMIN\listener.ora
    Listener Log File         C:\oraclexe\app\oracle\product\10.2.0\server\network\log\listener.log
    Listening Endpoints Summary…
    Services Summary…
    Service “CLRExtProc” has 1 instance(s).
    Instance “CLRExtProc”, status UNKNOWN, has 1 handler(s) for this service…
    Service “PLSExtProc” has 1 instance(s).
    Instance “PLSExtProc”, status UNKNOWN, has 1 handler(s) for this service…
    The command completed successfully

That’s it! That should resolve the problem. Verify by running “tnsping XE” or “tnsping dbname” at the command prompt. It should return OK.

All your tools like Toad, SQL Plus or Oracle SQL Developer should be able to connect to the database now!

Fixing the double-letterboxing effect in Windows Media Player…

To resolve the double-letterboxing effect when playing a widescreen (16:9) movie encoded as fullscreen (4:3) on a widescreen laptop: use Videolan.

Videolan is a freeware, open-source media-player that can help to resolve this problem by providing zoom and crop features that are easily accessible with a right-click while playing the video. If you have an older version, check out the newly released 0.9.* (Grishenko) release – it’s really cool!

Upgrade issues with Norton Antivirus

Here’s what to do if you’re trying to upgrade to Norton Antivirus 2008 and getting the dreaded error message: “Setup has detected that LiveUpdate or AutoLiveUpdate is running. Setup will now abort.”:

  • There is no easy way to kill the LiveUpdate processes or services once started. The only way around this is to prevent them from starting in the first place.
  • Go to Start > Run, type services.msc to bring up the Windows Services.
  • Find all the services that start with “LiveUpdate…”, “AutoLiveUpdate…” or “Symantec…” and right-click on each one of them and go to “Properties”.
  • Set the “Startup Type” to Disabled.
  • Restart your computer and the upgrade should go smoothly this time.

If you find a better way to do this, be sure to post it here for everyone’s benefit!