系统：Windows XP
SQL> select * from v$version;
BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
PL/SQL Release 11.2.0.1.0 - Production
CORE 11.2.0.1.0 Production
TNS for 32-bit Windows: Version 11.2.0.1.0 - Production
NLSRTL Version 11.2.0.1.0 - Production
用sql*plus登录数据库，收到了ora-28056 错误；
Microsoft Windows XP [版本 5.1.2600]
(C) 版权所有 1985-2001 Microsoft Corp.
C:\Documents and Settings\Administrator>sqlplus / as sysdba
SQL*Plus: Release 11.2.0.1.0 Production on 星期三 8月 7 17:05:19 2013
Copyright (c) 1982, 2010, Oracle. All rights reserved.
ERROR:
ORA-28056: Writing audit records to Windows Event Log failed
ORA-28056: Writing audit records to Windows Event Log failed
请输入用户名:
ERROR:
ORA-01017: 用户名/口令无效; 登录被拒绝
请输入用户名:
ERROR:
ORA-01017: 用户名/口令无效; 登录被拒绝
SP2-0157: 在 3 次尝试之后无法连接到 ORACLE, 退出 SQL*Plus
检查oracle服务存在，也启动了；于是就官网查看错误：
ORA-28056: Writing audit records to Windows Event Log failed
Cause: Unable to write an audit entry to the Windows event log used as the audit trail.
Action: Check the error number for a possible operating system error. If there is no error, contact Oracle Support Services.于是就把系统的“事件查看器”日志清除，Ok，搞定；
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