Hello I really stuck up in configuring Exchange behind ISA Server 2000. I consult throgth many documents including ISA Exchange Development Kit. According to my senario I have had three Machines one for ISA one for Exchange and one for DNS. When I try NSLOOKUP to check DNS it returned : C:\>nslookup dns Server: dns.ispengineering.homeip.net Address: 10.0.0.1 Name: dns.ISPEngineering.homeip.net Address: 10.0.0.1 C:\>nslookup hotmail.com Server: dns.ispengineering.homeip.net Address: 10.0.0.1 DNS request timed out. timeout was 2 seconds. DNS request timed out. timeout was 2 seconds. *** Request to dns.ispengineering.homeip.net timed-out C:\>nslookup mail Server: dns.ispengineering.homeip.net Address: 10.0.0.1 Name: mail.ISPEngineering.homeip.net Address: 10.0.0.2 C:\>nslookup hotmail.com Server: dns.ispengineering.homeip.net Address: 10.0.0.1 Non-authoritative answer: Name: hotmail.com Addresses: 64.4.33.7, 64.4.52.7, 64.4.32.7 On ISA server computer i managed server publishing rules for SMTP, POP3, Exchange RPC and DNS Query in site and content rule i allow DNS / SMTP SERVER to pass packets (as described in dev. Kit) plus "Allow All" rule (as i also use internet on local network) In protocol rules i make rules for DNS, Zone transfer and SMTP (as described in dev Kit) On exchange server computer I configure a SMTP virtual server configured to use external DNS Server plus a connector which use DNS to route to each address space & in advanced tag -- > selecting "Do not send ETRN/TURN" My exchage can recieved mail but can not able to send. When i send mail it remain in queue of SMTP virtual server(ConnecterName -- hotmail.com(SMTP Connector -- Remote Delevery) Retry Please help me out Ali Zubairy --------------------------------- Do you Yahoo!? Find out what made the Top Yahoo! Searches of 2003