1. use SVRMGRL
2. set your environment to the instance you want to log into
4. if CONNECT/INTERNAL is not working which mean that your password has changed.
5. If your password is changed and you don't know the password, change the password file at ORACLE_HOME\database\pwd.ora. what you need to do here is delete the old password and recreate the new one using ORADIM
In NT we must have ora_dba group . Programs/admin tools/user manger under that you can see ora_dba group . If he had logged to nT using any account under ora_dba group,he can be connected to oracle without any password or connect string ..Usually I won't use any password or connect string .. Just connect internal ,if prompted for password just return . Now on 9i release just connect sys as sysdba ..
Not trying to go off tangents follow these steps meticulously,
1. In configuration box(my computer) /services, you must have oraclestart and oraclestart start , if not start them.
2. start your TNSLSNR80 from services or thru cmd.exe prompt lsnrctl8x , then check status first ,if not started promt start.
3. Test your connection to the database , thry net8 utility.
create it if you didn't create it. Depending on how you created the instance(i prefer to use dbassistent , then custom creation helps you create you internal account...), but anyways keep all your passwords and test the connection here...
modify your lsnr.ora, tnsnames.ora files if required.
4. Tip:also check the registry, i prefer to have it clean from previous installations...
5. Let us know here if this worked.
I'm a JOLE(JavaOracleLinuxEnthusiast)
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