Forum Discussion
Why is Exchange 2016 using DNS A record instead of MX record to send mail?
Exchange 2016 trying to send mail to sargb.com. Instead of sending to their MX "sargb-com.mail.protection.outlook.com", it is sending mail to sargb.com (18.235.162.72). I cleared the DNS cache on t...
Exchange 2016 defaults to using DNS A records for direct delivery between servers. To force the use of MX records, you need to modify the send connector:
Set-SendConnector ConnectorName-UseExternalDNSServersEnabled $true -SmartHosts $null
and ensure that the DNS lookup settings are not checked to use external DNS options.