http://www.ISAserver.org Dear All, Let me describe my recent problem: Any client computers, which not using the firewall client program, can not ping to any external server by name. It always reply "unknown host". In Ms Outlook we can not use the name of the mail server for pop3 or smtp, it doesn't work. But surfing the website is working fine. The clients work fine if I switch to use its IP address. Other client computers which use firewall client are working fine. I use ms isa 2000 with sp2 on ms win 2000 server. Any help would be appreciating. Thanks Best regard, Krisna