to solve your problem i need few information from you.

1. is the database installed on your PC ?
2. are you trying to log in to a database in a network ?
3.is the scott user exists and and is unlocked ?

create user scott identified by tiger ;

to do that you need to log in first and normal users can't create another user .

This error

ERROR: ORA-12154: TNS:could not resolve service name

only appears when you don't have an instance of a database or you don't have the listener on.

Make sure you have the DB online and the listener.

You can view the listener status with: 'lsnrctl status' and start it with 'lsnrctl start'.

When the listener is running, you can enter as sysdba (defined when the DB is installed) and type an 'startup' command to start the database you have define. Use 'startup db_sid' if you have more than one.

Hope it helped.

check scott is unlock or not ............
& for system ...........
did you change the password at the time of installation or not.......

At the end of instalation programs diplay a screen with name password managemant. You just go to password management screen anf unblock all the users anf=d just fix your user and password.

Hey this is surely a problem of uncloking the users bt once check out if u have enabled the serices of oracle installed

Er guys, SqlPlus 3.3.4.0.0? Isn't this from the days of Oracle 7?

I would think we would need to know more about your config before we could really help!

client / server, versions of oracle and client, where components are installed etc.

Your error suggests that the oracle client components are not installed / not in the path / wrong oracle_home selected - to name but a few possibilities!

Alistair

Oracle 11g sql plus it show account is locked it showing enter user name &password