Some dial-in options for user accounts in the Active Directory may be unavailable. This occurs when Active Directory is in Mixed mode.

The following options are unavailable while the Active Directory is in Mixed mode:

•	Control access through remote access policy
•	Verify caller ID
•	Assign a static IP address
•	Apply static routes
•	Static routes

To enable these options, change the Active Directory to Native mode. Note that when you change the Active Directory from Mixed mode to Native mode, it cannot be reversed. Native mode does not allow down-level domain controllers to participate in the Active Directory. Microsoft Windows NT 3.51 and 4.0 backup domain controllers (BDCs) do not synchronize with the Windows 2000 primary domain controller (PDC) in Native mode. After you upgrade all the domain controllers to Windows 2000, you may want to consider changing the Active Directory to Native mode.

For additional information about the modes supported by Windows 2000, please see the following article in the Microsoft Knowledge Base: