I have implemented a new Exchange 2007 server running on Server 2008 in our domain. We previously used Exchange 2003 running on Server 2003 and I had locked the Default SMTP Connector down so that it would only accept message from a range of IP addresses provided by MX Logic. For those who don't know, MX Logic provides spam filtering services, like Postini.
I have added the MX Logic IP addresses to the IP Allow List under Server Configuration > Hub Transport. My question is, how do I tell the Exchange server to deny messages from all other IP addresses that are not explicitly defined in the IP Allow List?
If it matters, this server is the Client Access Server and Hub Transport server. We do not have an Edge Transport server in the organization.