TNS-12541: TNS:no listener but Windows TNS Listener Services is Started

Hi Experts,

Somehow, our database instance is not able to connect to the database instance when no any Oracle server files were modified, listed below :

Database Instance : UP, Listener : DOWN, Agent Connection to Instance : DOWN

When run this command using sql plus :

select value from v$parameter where name='service_names';

The output is : orcl1

Here's my listener.ora (D:\Oracle\product\11.2.0\dbhome_1\NETWORK\ADMIN) :

LISTENER =
 (DESCRIPTION_LIST =
  (DESCRIPTION =
   (ADDRESS = (PROTOCOL = TCP)(HOST = XXXDS1)(PORT = 1521))
   (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
  )
 )
ADR_BASE_LISTENER = c:\Oracle

tnsnames.ora :

ORCL1 =
 (DESCRIPTION =
  (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.12)(PORT = 1521))
  (CONNECT_DATA =
   (SERVER = DEDICATED)
   (SID = ORCL1)
   (SERVICE_NAME = ORCL1)
  )
 )