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TitanHQ Product Docs

Locking Down Your Office 365 Mail Server

Notice

The instructions below include information about tools that are not owned or managed by TitanHQ and are only intended as a guideline to help you. As such, the information may be subject to change without us knowing.

If you notice anything out of place, please email docs@titanhq.com and let us know.

Follow the steps below to lock down your inbound email flow in Office 365 to only accept email from your SpamTitan. This requires you to create a receive connector in Office 365.

  1. Log in to your Office 365 Exchange Admin Center (EAC).

    Note

    If you are using Microsoft 365 Defender, log in to security.microsoft.com and select Exchange message trace from the sidebar menu to open your Exchange Admin Center.

  2. Select Mail flow and then Connectors from the sidebar menu to view your connectors.

  3. Select ST-701-office365-add-button.jpg Add a connector and the New connector window displays. Select Partner organization as shown:

    ST-O365-new-connector.jpg
  4. Select Next and the Connector name window displays. 

  5. In the Name field, give the connector a meaningful name. For example, SpamTitan to Office 365. Select Next.

  6. In the Authenticating sent email window:

    1. Select By verifying that the sender domain matches one of the following domains.

    2. Enter * in the dialog box and select ST-O365-blue-add-button.jpg.

      ST-O365-authenticating-sent-email.jpg
    3. Select Next.

  7. In the Security restrictions window:

    1. Select Reject email messages if they aren't sent over TLS.

      Important

      This option requires that outbound TLS is enabled in SpamTitan.

    2. Select Reject email messages if they aren't sent from within this IP address range and enter your SpamTitan IP address. See SpamTitan Servers.

    3. Select ST-O365-blue-add-button.jpg to save the IP you entered:

      ST-O365-security-restrictions.png
    4. Select Next.

  8. The Review connector page displays the information you entered above. After verifying the information is correct, select Create connector.