PL/SQL客户端连接oracle11g出现提示ORA-12514:错误解决方法

ora-12514:TNS:监听服务当前无法识别描述中的请求服务 
原因：没有注册监听器 
解决办法： 
D:\app\Administrator\product\11.2.0\dbhome_1\NETWORK\ADMIN中的listener.ora修改如下所示： 
# listener.ora Network Configuration File: d:\app\Administrator\product\11.2.0\dbhome_1\network\admin\listener.ora 
# Generated by Oracle configuration tools. 

SID_LIST_LISTENER = 
  (SID_LIST = 
    (SID_DESC = 
      (SID_NAME = CLRExtProc) 
      (ORACLE_HOME = d:\app\Administrator\product\11.2.0\dbhome_1) 
      (PROGRAM = extproc) 
     
    ) 
  ) 
(SID_DESC = 
(GLOBAL_DBNAME = ORCL) 
(ORACLE_HOME = d:\app\Administrator\product\11.2.0\dbhome_1) 
(SID_NAME = ORCL) 
)  LISTENER = 
  (DESCRIPTION_LIST = 
    (DESCRIPTION = 
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521)) 
      (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521)) 
    ) 
  ) 

ADR_BASE_LISTENER = d:\app\Administrator 
加黑体部分，如果有(ENVS = "EXTPROC_DLLS=ONLY:d:\app\Administrator\product\11.2.0\dbhome_1\bin\oraclr11.dll")这句，请去掉，重启OracleOraDb11g_home1TNSListener服务，就可以了