Office 365 SMTP Work Around
Microsoft recently made a change to SMTP Authentication that has been blocking sending emails in TDO. Working with one of our partner IT firms, they were able to identify a process to work around this change. Following the steps listed under this Microsoft Article (Option 3), they were able to get things working again. Below is a summary of those steps:
- Make sure each TDO office has a static public IP address. You will need to get the public IP address for the MX Connector and the SPF record.
- Access the Microsoft 365 admin center
- Under domains, find the MX record and note the endpoints
- go to Exchange Admin Center > Mail Flow > Connectors. Select old or new connectors and link the endpoint to the office's static IP address
- add an SPF record to the domain that looks like < v=spf1 ip4:10.5.3.2 include:spf.protection.outlook.com ~all >. you will need to add an ip4: ip address for each office that will be sending out emails with the relay.
- Then configure the new relay in TDO email settings.
Device or application setting Value Server/smart host Your MX endpoint, for example, yourdomain-com.mail.protection.outlook.com Port Port 25 TLS/StartTLS Enabled Email address Any email address in one of your Microsoft 365 or Office 365 verified domains. This email address does not need a mailbox.
This is just a summary of the full steps shown in https://docs.microsoft.com/en-us/exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-microsoft-365-or-office-365#option-3-configure-a-connector-to-send-mail-using-microsoft-365-or-office-365-smtp-relay. For a full steps of how to setup your email, please consult that link or call Microsoft support.