ORA-27101: shared memory realm does not exist 错误的处理

　　我的Oracle 11g数据库下班之前还用得好好的，回到家之后打开笔记本电脑，通过PL/SQL连接确提示“ORA-27101”错误。

　　打开服务管理器，发现服务都启动了。重启服务也无济于事。

　　查看D:\Oracle11g\product\11.2.0\dbhome_1\database下的oradim.log日志文件，发现：

Thu Dec 20 18:36:40 2012
D:\Oracle11g\product\11.2.0\dbhome_1\bin\oradim.exe -startup -sid orcl -usrpwd *  -log oradim.log -nocheck 0 
Thu Dec 20 18:37:08 2012
ORA-28056: Writing audit records to Windows Event Log failed
OSD-1917408: Message 1917408 not found;  product=RDBMS; facility=SOSD

O/S-Error: (OS 1502) ??????????????????
ORA-28056: Writing audit records to Windows Event Log failed
OSD-1917408: Message 1917408 not found;  product=RDBMS; facility=SOSD

O/S-Error: (OS 1502) ??????????????????

　　打开事件查看器，清空了里面的事件，同时修改了D:\Oracle11g\product\11.2.0\dbhome_1\NETWORK\ADMIN写的sqlnet.ora文件：

　　修改前：

# sqlnet.ora Network Configuration File: D:\Oracle11g\product\11.2.0\dbhome_1\network\admin\sqlnet.ora
# Generated by Oracle configuration tools.

# This file is actually generated by netca. But if customers choose to 
# install "Software Only", this file wont exist and without the native 
# authentication, they will not be able to connect to the database on NT.

SQLNET.AUTHENTICATION_SERVICES= (NTS)

NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)

　　修改后：

# sqlnet.ora Network Configuration File: D:\Oracle11g\product\11.2.0\dbhome_1\network\admin\sqlnet.ora
# Generated by Oracle configuration tools.

# This file is actually generated by netca. But if customers choose to 
# install "Software Only", this file wont exist and without the native 
# authentication, they will not be able to connect to the database on NT.

SQLNET.AUTHENTICATION_SERVICES= (NONE)

NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)

　　重启服务，ok。