In Oracle 11G R2 the PASSWORD_LIFE_TIME option in defaul profile, which is the lifetime of the option password is usually defined as 90 days.
To disable users of password expiration option (default in Oracle 11G R2), just change the default profile as follows:
– Connect to the database server (open the sqlplus prompt):
$ sqlplus / nolog
– Log in as the SYS SYSDBA:
SQL> conn / as sysdba
– Run the command:
SQL> Alter profile default limit PASSWORD_LIFE_TIME unlimited;