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Troubleshoot Sophos Mailflow

If you have successfully set up Sophos Mailflow for a domain, the domain will display a green tick with a Connected status under Mailflow Connection. Similarly, for Post Delivery connection, the status will be a green tick with a Connected status under Post Delivery.

Sophos Mailflow connected.

If the domain is disconnected, you’ll see a red cross sign (x) with a Not Connected status. When you hover, a green tick appears. You can click this green tick to reconnect the domain.

Sophos Mailflow disconnected.

If a transport rule or connector has been updated from M365 directly that could impact Sophos Mailflow, the status will change to exclamation mark (!) with View Details status. For details, see Sophos Mailflow Tamper.

Sophos Mailflow View details.

Connections between Sophos Mailflow and Microsoft 365 domains may fail. For example your Microsoft 365 domain settings may change, preventing connections.

If you have problems with Sophos Mailflow, you can test a connection.

If the test fails, you can disconnect a domain, and then reconnect it.

Test a connection

To test a Sophos Mailflow connection, do as follows:

  1. Go to My Products > General Settings > M365 Mailflow Domain Settings / Status

  2. Click the test icon for the domain you want to test.

    Run a Test icon in Domain Settings/Status.

  3. In Run a Quick Test, enter an email address to receive a test email.

  4. Click Proceed.

    The test takes a few minutes.

If the test fails, you can click Run The Test Again or Reconnect.

If the test still fails, or you can't reconnect, you can manually disconnect then reconnect the domain.

Disconnect a domain

To disconnect a Sophos Mailflow domain from your Microsoft 365 domain, do as follows:

  1. Go to My Products > General Settings > M365 Mailflow Domain Settings / Status.

  2. Find the domain, hover on the Connected status, and click the cross (x).

    This removes the apps, connectors and rules that Sophos Mailflow created in your Microsoft 365 environment for that domain. It might take a few minutes.

You can check that everything has been removed before reconnecting the domain.

Check your Microsoft 365 settings have been removed

If you've disconnected a domain and want to check that everything has been removed from Microsoft 365 before reconnecting it, you can review the apps, connectors, and rules in your Microsoft 365 admin center.

Note

We recommend you check Microsoft help for updates before changing your email configuration.

To check your Microsoft 365 settings, do as follows:

  1. Sign in to your Microsoft 365 admin center.
  2. Go to your Microsoft Entra ID admin center and click App registrations.
  3. Check that the Sophos Email Mail flow app for the domain that you are troubleshooting is removed.
  4. Go to your Exchange admin center.
  5. Go to Mail flow and click Rules.
  6. Check that the rules that redirect inbound and outbound emails to Sophos for that domain are removed.
  7. Go to Mail flow and click Connectors.
  8. Check that the connectors for inbound and outbound emails for that domain are removed.

For more information about the changes made when you connect Sophos Mailflow to your Microsoft 365 environment, see Rules and connectors created in M365.

Reconnect your domain

Now reconnect your Microsoft 365 domain to Sophos Mailflow.

See Set up Sophos Mailflow.