Customizing user login
In the default setup the Drupal login block is always displayed unless a user is logged in. This may not always be desirable. For example, if you are using Drupal to create a site that has a very small number of people actually logging into the system to create or edit content, then you probably don't want a large portion of your screen real-estate taken up with a login block that doesn't relate to them. This also confuses the majority of your users that will not have the option to login.
To disable the login block:
- Goto the block configuration (administer » blocks)
- Deselect the check box for User login in the Enabled column
Your regular content editors and administrators can still login to the site by directly accessing the login page, http://www.example.com/?q=user. If you are using clean URLs you may also use http://www.example.com/user, but remember that the ?q=user version will always work whether you have clean URLs enabled or not.
You can also create more customized login blocks.
You can create name and email filter rules in admin >> access control >> account rules.
Set up username and e-mail address access rules for new accounts. If a username or email address for a new account matches any deny rule, but not an allow rule, then the new account will not be allowed to be created.