I have a client that has a random problem sending mail out of Exchange 2000. The mail will sit in the SMTP queue and eventually ends up with NDR’s. The message returns as an Internal DNS error prevented delivery of the message. I have looked thiserror up and have found the problem only relating to ISA server which they do not run. They have Internet access through a wireless provider and are not given an external IP nor actual DNS servers to query. We are instructed to use the Gateway/Firewall’s address as the DNS server and are able to browse the internet fine. As a result the server is unable to ping hosts such as www.microsoft.com. Mail will work for a month and then quit, last time they had this problem I restarted the DNS Client service and the mail moved freely. This time we have rebooted the server and the mail still sits undeliverable.
Win2000 SP2 Exchange 2000 SP1
Thanks