oracle登陆不上去了

C:\Documents and Settings\Administrator>sqlplus / as sysdba

SQL*Plus: Release 10.2.0.2.0 - Production on 星期二 8月 24 11:06:20 2010

Copyright (c) 1982, 2005, Oracle.  All Rights Reserved.

ERROR:
ORA-01031: insufficient privileges

Enter user-name:

============================

这样才能上去：

C:\Documents and Settings\Administrator>sqlplus sys/ as sysdba

SQL*Plus: Release 10.2.0.2.0 - Production on 星期二 8月 24 11:07:08 2010

Copyright (c) 1982, 2005, Oracle.  All Rights Reserved.

Enter password:【****】

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - Production
With the Partitioning, OLAP and Data Mining options

SQL>

什么原因？

可能为了禁止了os身份验证方法了，
看看sqlnet.ora里面的sqlnet.authebtication_serivces是否等于(none)，如果是的话，把(none)改为(nts)试下

直接输入： CONNECT sys/密码 AS SYSDBA