Oracle 11g default profile default Enable Password Expiration 180 days ORA-28001 error handling

Problem description: the customer reports that the client cannot connect when it cannot log on to the application.
Environment: AIX 5.3 + Oracle 11gR2
Solution: remote Telnet to the Database Host, sqlplus/as sysdba after the connection operation is normal, indicating that the database server should be normal, and then in the client to connect to the database with sqlplus prompt Password Expiration error: ORA-28001: the password has expired. It turns out that the password has expired.
Analysis: in Oracle versions earlier than 11g, the default profile has no password expiration restrictions. In Oracle 11g, the default profile enables the password expiration time to be 180 days. You can remove this restriction.

Query the Password Expiration settings of the default profile.
Select * from dba_profiles
Where profile = 'default' and resource_name = 'password _ LIFE_TIME ';

Set the default profile password to never expire. It takes effect immediately and does not need to be restarted.
Alter profile default limit password_life_time unlimited;

You need to change the Expired Password.
If you can log on with sqlplus, you will be prompted to change the password.
You can also alter user username identified by password;