文档介绍：在用PL/SQLDeveloper连接数据库时出现“ORA-12541:TNS:无监听程序”错误。1、 :TNSLSNRfor32-bitWindows:-Productionon20-9月-200810:25:26Copyright(c)1991,2005, 统参数文件为D:\orac1e\product\\work\admin\:\oraclc\product\\db_l\nctwork\log\:\oracle\product\\work\trace\ _跟踪级别当前为0以pid=1704开始监听 :(DESCRIPTION(ADDRESS=(PR0T0C0L=ipc)(P1PENAME=\\.\pipe\EXTPROClipc)))监听该对象时 ;1! 错 :(DESCRIPTION二(ADDRESS二(PROTOCOL二TCP)(HOST=)(P0RT=1521)))TNS-12545:因目标主机或对象不存在,连接失败TNS-12560:TNS:协议适配器错谋TNS-00515:因目标主机或对象不存在,连接失败32-bitWindowsError:49:Unknownerror不再监听:(DESCRIPTION(ADDRESS=(PR0T0C0L=ipc)(PIPENAME=\\.\pipe\EXTPROClipc)))2、查看Oracle的listener是否启动C:\DocumentsandSettings\mengzhaoliang>lsnrctlstatusLSNRCTLfor32-bitWindows:-Productionon20-9月-200810:50:44Copyright(c)1991,2005,(DESCRIPTION二(ADDRESS=(PROTOCOL=IPC)(KEY二EXTPROC1)))TNS-12541:TNS:无监听程序TNS-12560:TNS:协议适配器错误TNS-00511:无监听程序32-bitWindowsError:2:Nosuchfileordirectory止在连接到(DESCRIPTION(ADDRESS二(PROTOCOL二TCP)(HOST=)(PORT二1521)))TNS-12535:TNS:操作超时TNS-12560:TNS:协议适配器错误TNS-00505:操作超时32-bitWindowsError:60:Unknownerror原来没有启动listener,用ulsnrctlstart命令也不能启动。C:\DocumentsandSettings\mengzhaoliang>lsnrctlstartLSNRCTLfor32-bitWindows:-Productionon20-9月-200810:52:16Copyr