I have a customer who has Exchange 2003 that has had problems sending email to a particular organization. When I followed up with this organization they said the following.
I have checked our mail relay logs and the problem is the FQDN your mail server is providing when connecting to our relay server.
Currently your server is configured to send servername.local which cannot be resolved outside of your local system. The correct response from your server would be mail.domainname.org.au as this address can be correctly resolved.
Please pass this advice to your IT team, as once this is corrected you should again be able to send to ahl.gov.au addresses.
Can someone explain what I need to do to resolve this matter, as we have been using this server for 4 years without a problem til now