checklist:
1.12c: threaded_execution=true Prevents OS Login As Sysdba
2. The following database parameter should be set either to SHARED or EXCLUSIVE and not NONE : remote_login_passwordfile=EXCLUSIVE
3. On Windows, Set the following Sqlnet parameter in <ORACLE_HOME>/network/admin/sqlnet.ora file: SQLNET.AUTHENTICATION_SERVICES=(NTS)
4. ues install user to loging () On MS Windows NT/2000/2003/XP:
On MS Windows the OSOPER and OSDBA groups are hard coded groups thus: Group Name Oracle uses this as... ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~ ORA_OPER OSOPER group for all instances ORA_DBA OSDBA group for all instances or ORA_sid_OPER OSOPER group for a specific Oracle SID ORA_sid_DBA OSDBA group for a specific Oracle SID When you issue a 'CONNECT / AS SYSDBA' , Oracle checks if your MS Windows logon is a member of the 'ORA_sid_DBA' or 'ORA_DBA' group.