Hi all, please, how to configure firewall (which is not in domain) and Exchange 2k Server (with internal IP) to allow external client access to their mailboxes? I have already set: Exchange 2k Server - Active Directory\Users\Properties\Dial-in\Remote Access Permission (Dial-in or VPN)\Allow access & No Callback ISA Server (firewall & proxy server, not in a domain) - Access Policy: Mail wizard rule SMTP, SMTPs outgoing smtp, pop3, imap4 ssh, imcp, dns + IP Packet filters VPN (PPTP, L2TP), DHCP, DNS, ICMP I was trying also to configure Outlook account with external IP of firewall = Outlook could not logon. Is VPN configuring both client and servers only way to resolve it? And how? Thank for any advice.