Hi,
I am using an external hosted spam filter to filter out spam and virusses, the mx of my domain point to the spam filter and the filter in turn deliver the mail to my server. however some spam are still being sent directly to the server bypassing the filter, even if the hostname of the server is no lomger listed as a MX record in the DNS. Is there a way I can set the server to only allow receiving email from certain ip addresses (in this case the ip addressess of the spam filter)?