My ISP has issued a public IP address to be used by my exchange server. However, when I send an external e-mail it bounces back as Undeliverable: The following organisation rejected your message:SMTP smarthost address.
I have spoken to them and they have said that the smarthost will only accept to relay if the e-mails appears to be coming from the public IP they issued me. My exchange sits behind and ISA 2006 server and I have specified the Internal IP of the Exchange Server in the 'This rule applies to traffic From and in Traffic to I have set that to external. But when I send e-mails to external recipients, I get a"SmartHost #550 Relaying not permitted (3.7).
Where in ISA 2006 do I specify the public IP address as Natting for outbound traffic does not seem to be available on ISA.
Also, is there a way for me to find out what IP the smarthost is seeing my e-mail as coming from?