Mail Server IP Range
System notifications from our system are going to our junk email folder and are not being seen until someone follows up with the receiver at a later date. We would like to add an rule on our inbound mail filter to allow these notifications to come through. However, I am unsure as to the exact range we should use. From the email headers of these emails, they appear to be coming from 126.96.36.199 (smtp.sapbydesign.com), however they also appear to be going through an outgoing mail relay, expurgate.net.
Does anyone know what the correct mail server IP range is to add to our conditional rule?
Thanks in advance,