Managed Client: Unable to configure automatic login setting in System Preferences
In Mac OS X v10.5 and later, if an administrator is managing the Login: Options view in Workgroup Manager, the automatic login feature will be dimmed ("grayed out") in System Preferences.
This can happen when automatic login is managed via Workgroup Manager. To allow a user to configure this setting, use either of the following methods below:
As an admin user, log in holding the Option key to force the Workgroup Picker window to appear. If allowed, disable the "Enable Workgroup management" checkbox to bypass preference management. Once logged in, configure the automatic login setting in System Preferences.
or
In Workgroup Manager, choose to manage the "Login: Options" view Never. Configure the client's automatic login feature. and then reconfigure your managed settings in Workgroup Manager.
Once a user has been configured to automatically log in, this setting will be respected when managed.