Hi Thanks to anyone who can help. Our Exchange Server (part of SBS2003) is currently sending e-mail via our isp's smtp server. This has become problematical because our isp is not allowing enough throughput (they limit to a maximum of 50 receipients in one hour), so we investigated the other setting which is to use DNS. Just to be absolutely clear, we switched from “Forward all mail through this connector to the following smart host” to “Use DNS to route to each address space on this connector”. When we do this, e-mails just sit in the outbound queue and do not get sent. My understanding is that using the DNS method bypasses our ISP and our server tries to send directly to the recipients domain. If my understanding is correct this is obviously a bit more complicated than just 'flicking the switch'. Firstly, is my understanding correct and secondly, if it is, what else needs to be done? Also, are there any potential problems that might arise from the DNS method if we can get it working?

1. Check the firewall to ensure it allows DNS queries and SMTP ( Port 25) through it to any destination. ( Rather than simply allowing port 25 to the ISP) 2. Does your ISP allow you port 25 to any destination?

Hi Trcikey300, I am bit doubts about your configuration. There is two option to send outbound mail a) Use smart Host b) Use DNS lookup. If you want bypass your ISP as smart host then you should just use any external DNS to send mail to internet and not smart host option. Is it make sense to you ? Correct me if i understand your situation here.Anil