How do I set up Exchange Online (Microsoft 365) to send messages via the outgoing filter?

Log in to the admin panel of EuropeanMX as a domain admin. You can find instructions in our FAQ article "How can I log into the Admin panel (web interface of the filter)?".

Select Outgoing and then Manage users.

Select the tab Authenticating Domain and make sure that the domain name you manage in Exchange Online is specified there.

Enter a secure password and then select Add and configure from the drop-down menu.

In the outgoing user's settings, enable the option Re-authentication allowed: and make the desired settings. In our FAQ article "How do I set up an outgoing user?" you can find more information about the settings.

Log into the admin center of Microsoft365.

Select Show All in the navigation menu.

Click on Exchange to enter the Exchange Administration Center.

Click on Mail flow and select Connectors.

Then click + Add a connector and set the following settings:

• Set the connection from: Office365
• Set the connection to: Partner organization

Click on Next.

Assign a name for the connector (e.g. "EuropeanMX Outgoing filter") and click Next".

On the Use of Connector window, select Only when I have a transport rule set up that redirects messages to this connector and click Next.

Select Route email through theses smarthosts and enter smtp.antispamcloud.com.

Click the plus sign (+) and then click Next.

Ensure that the option Always use Transport Layer Security (TLS) to secure the connection (recommended) is activated in the tab Security Restrictions.

• Use Issued by a trusted certificate authority (CA).
• Then click Next.

Enter a valid email address in the field Validation email.

Click the plus sign (+) and then click Validate.

Once the email has been validated, click Next.

Check the details of the connector again and then select Create connector.

Log in to the Microsoft365 Administration Center.

Navigate to the Exchange Administration Center in the left menu.

Select Mail flow and then Rules.

Add a new rule via the plus sign (+).

Click on More options at the bottom of the window.

Assign a name for this rule (e.g. "EuropeanMX outgoing").

Fill in the fields as follows:

• Apply this rule if the sender's domain is IHREDOMAIN.TLD: Specify your domain(s) in the popup and click the plus sign (+) if necessary to add each one.
• Do the following: Redirect messages to the following connector: In the popup dropdown menu, select the connector you created in the 2nd step.
• Except if: The recipient is internal/external: Select Inside the organization from the popup.
• Choose a mode for this rule: Enforce

Click Save to save the rule.