The Automatically log off users when logon time expires, at Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options, should be re-titled as Automatically disconnect users when logon time expires.

This policy affects the Server Message Block (SMB) component of a Windows 2000 server. When the policy is Enabled, the client sessions with the SMB server are forcibly disconnected when the client's logon hours expires.

NOTE: This policy affects all the computers in the domain, unlike Automatically log off users when logon time expires (local), which only affects the computers upon which it is applied.

NOTE: See tip 3468 » When you configure a user's Logon Hours, they are not disconnected when the time expires?

NOTE: See tip 5566 » When you enforce logon hours restrictions, users are NOT forced off?