I have an Oracle 11g server that's used for PHP development. Recently, I had a problem logging into the Enterprise Manager due to expired passwords. I've already changed settings so passwords no longer expire and I've unlocked all users. However, the user manager shows most built-in users as expired. How can I fix that? (If I just set a password for each expired account I guess that whatever services are using it will no longer be able to log in.)
ALTER USER user ACCOUNT UNLOCK;
If you want that the user is no longer expired you have to change the password (as far as i know). Anyway for those system users is pretty normal they're expired and locked. Instead here http://download.oracle.com/docs/cd/B28359_01/server.111/b28337/tdpsg_user_accounts.htm he's suggesting to change immediately default passwords (as normal procedure) and the users are locked down for security reason.
Are these users using the "default" profile ? If so, maybe you can check what are the policies attached to this policy ?