ORA-12514 : TNS:监听程序当前无法识别连接描述符中请求的服务
一、找到监听文件，添加红色部分代码即可,如下：

# listener.ora Network Configuration File: E:\oracle\product\10.1.0\db_1\network\admin\listener.ora
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PLSExtProc)
      (ORACLE_HOME = E:\oracle\product\10.1.0\db_1)
      (PROGRAM = extproc)
    )
    (SID_DESC =
      (SID_NAME = orcl)
      (ORACLE_HOME = E:\oracle\product\10.1.0\db_1)
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC))
      )
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))
      )
    )
  )

二、执行命令

C:\Documents and Settings\Administrator>lsnrctl stop
.
.
.
C:\Documents and Settings\Administrator>lsnrctl start