ORA-12514 is occurs when following condition is not meat
1) Mismatch of TNS in oracle installation Directory (tnsnames.ora file)
(ADDRESS = (PROTOCOL = TCP)(HOST = “server ip”)(PORT = 1521))
(SERVICE_NAME = “dbname”)
2) Spelling mistake in above configuration
3) Database is not found on tnsnames.ora file as HOST = “server ip”.
To check which database is available on server as bellow step
- Open cmd
- sqlplus user/psw
- select name from v$database;
- Check TNS database name in tnsnames.ora and the output database of above common is not equal then it generate ORA-12514 error.