title: ORA 12514 error:TNS listener error
body: <p>Ok everything worked fine till yesterday now i am suddenly getting this error <br>
  ORA-12514: TNS:listener does not currently know of service requested in connect descriptor<br>
  nothing had been modified</p>
  
  <pre><code>XE =
    (DESCRIPTION =
  (ADDRESS = (PROTOCOL = TCP)(HOST = jainam-2b1c493d)(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) 
   ) 
  ) 
  </code></pre>
  
  <p><br>
  I am totally stuck and have no idea what to do.
  I tried help from here <br>
  <a href="http://dba-oracle.com/t_ora_12514_tns_listener_does_not_currently_know_service_requested.htm" rel="nofollow">http://dba-oracle.com/t_ora_12514_tns_listener_does_not_currently_know_service_requested.htm</a>
   but no use.
  Thanks</p>
  
  <p><br>
  EDIT:
  <br>
  here's the output to <code>lsnrctl service</code><br><br></p>
  
  <pre><code>Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1)))
  Services Summary...
  Service "CLRExtProc" has 1 instance(s).
    Instance "CLRExtProc", status UNKNOWN, has 3 handler(s) for this service...
      Handler(s):
        "DEDICATED" established:0 refused:0
           LOCAL SERVER
        "ORACLE SERVER" established:0 refused:0 current:0 max:25 state:ready
          CLRExtProc
       (ADDRESS=(PROTOCOL=ipc)(PIPENAME=\\.\pipe\NTN_6B4_641B624E_B22.ORA))
    "ORACLE SERVER" established:0 refused:0 current:0 max:25 state:ready
       CLRExtProc
       (ADDRESS=(PROTOCOL=ipc)(PIPENAME=\\.\pipe\NTN_6B4_641B624E_282.ORA))
  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 "XEXDB" has 1 instance(s).
   Instance "xe", status READY, has 1 handler(s) for this service...
   Handler(s):
    "D000" established:0 refused:0 current:0 max:1022 state:ready
       DISPATCHER &lt;machine: JAINAM-2B1C493D, pid: 3708&gt;
       (ADDRESS=(PROTOCOL=tcp)(HOST=jainam-2b1c493d)(PORT=2763))
  Service "xe" has 1 instance(s).
  Instance "xe", status READY, has 1 handler(s) for this service...
  Handler(s):
    "DEDICATED" established:0 refused:0 state:ready
       LOCAL SERVER
  The command completed successfully
  </code></pre>