Obtain Windows 7 system administrator privileges again

Background: After the Windows 7 system is reinstalled, A user A is created and added to the Company domain. (The Administrator user is also created after the system is reinstalled. I don't know the password ), this user A belongs to the administratos group and uses this account for normal work, including user A when installing the oracle database. I want to review sqlplus yesterday .. All kinds of problems are reported. After the ORACLE_SID = ORCL environment variable is set (two databases are installed on the local machine), although some problems are solved, it is always unable to log on as sysdba.
Www.2cto.com
Later, I checked the information and found that sqlnet. ora in windows contains SQLNET. AUTHENTICATION_SERVICES = (ETS), which indicates that oracle uses windows user authentication. View your user permissions, belong to the Administratos group, and change it to the ora-dba group. After logging out and logging on again, sqlplus can log on to the system through sysdba! However, the logged-on user is not in the Administratos Group. As a result, many programs run with prompts to enter the user name and password of the system administrator. However, I do not know the password of the system administrator Administratos, but only the password of the currently logged-on user.
Www.2cto.com solution: 1. Use winPE unzip cmd.exe osk.exe Asus to enter the startup page through esc. Other computer legends are that F12 enters the startup page and then enter c: cd c: In the pop-up window: \ windows \ system32ran.exeand osk.exe follow these steps to restart the operating system to enter the logon page. Click the application to enter the cmd command line, and the cmd working directory is c: \ windows \ system32, and then execute: net user, you can see that there is an account Administrator and then execute the net user Administrator password (re-give the Administrator a new password) net user Administrator/active: yes (activate the Administrator user) then you can log on to the system through Administrator. After logging in, Change User A's group to Adminstrators.