Your network contains an ISA Server 2006 computer named ISA1 operating in a Workgroup. ISA1 functions as a remote access VPN server for the network. Remote access VPN clients can use either PPTP or L2TP over IPSec to connect to ISA1. Users report that after connecting to the corporate network, they cannot access file shares on the network file server without first being presented with an authentication prompt. You need to ensure that users are not asked for credentials when they access file shares. Which two actions should you perform? (Each correct answer presents part of the solution. Choose two.)

A.
Instruct the users to log on by using their domain credentials via dial-up networking.

B.
Configure ISA1 as a RADIUS client.

C.
Create an access rule to enable the LDAP and LDAPS protocols from the Local Host network to the Internal network.

D.
Join ISA1 to the domain.