Microsoft Exchange Outbound Filtering Setup for Spam Experts

All references of SMARTHOST need to be replaced with the Spam Experts SMTP hostname, see this page for full details.

Exchange Online (Local Cloud Only)

  1. Configure secondary IP for port 25 outbound. See Outbound Filtering Hostnames

    You must configure the use of port 25 for outgoing email, and specify a secondary IP which will be configured to listen to port 25 for outgoing connections and then will be required to update the sending servers relay hostname.

    Using port 25 is not recommended for outgoing mail. You should also restrict outgoing mail in your firewall to stop bad actors or malware from sending mail from your IP addresses.

    Please contact Spam Experts support for assistance

  2. Create a hostname with this secondary IP using port 25 for the outbound connections as an A record

    For example: office365.yourcluster.invalid

  3. Add a domain in Spam Experts where all Exchange Online IPs can be added as Authorizing IP users, ensuring you select Sender Domain selected for the Re-authenticate as field

    A list of Exchange Online SMTP IPs can be found on the Microsoft documentation: Office 365 URLs and IP address ranges. Only IP's used for SMTP are required, please contact your provider for details if required.

  4. Subsequent domains should then be added using the Configure Outgoing Filtering with Exchange Online (Microsoft 365) process using Authenticating Domain and enabling Re-authentication permitted

Exchange 2013/2016/2019

Routing all outgoing mails via the outgoing smarthost:

  1. Ensure the IP address is added as an authorized smarthost (without authentication)
  2. Ensure the outgoing user has correct limits set matching your traffic volumes
  3. Update your configuration

A Send Connector must already have been created and configured correctly in Exchange Administration Center:

  1. Navigate to Mail Flow
  2. Select Send Connectors
  3. Select + Add new connector
  4. Add a relevant name for this connector, Eg: Spam Experts Outgoing Filtering
  5. Select : Internet (For example, to send internet mail) and click Next
  6. Select Route mail through smart hosts
  7. Add the SMARTHOST by clicking on the + sign
  8. Click Save
  9. Click Next
  10. If you are using an IP outgoing user leave None / If you are using an Authenticating user select Basic Authentication > Input the Outgoing User and Password
  11. Click Next
    1. Address space: Click the + sign and in the Full Qualified Domain Name (FQDN): input
  12. Click Save and Next
  13. Source server: Click on the + sign and select the server from the list
  14. Click OK and Finish

You need to ensure that the port 587 is being used:

  1. Open the Exchange Management Shell
  2. Run the following:

    Set-SendConnector -identity "NAME OF CONNECTOR" -Port:587

Exchange 2007/2010

Versions 2013 and earlier of exchange have reached the official End-of-Life (EOL) with Microsoft and Microsoft has ceased support for these products. The following instructions were correct at time of writing, however, as these versions are no longer officially supported, we cannot guarantee the success of configuration.

Routing all outgoing mails via the outgoing smarthost:

  1. Ensure the IP address is added as an authorized smarthost (without authentication)
  2. Ensure the outgoing user has correct limits set matching your traffic volumes
  3. Update your configuration. A Send Connector must already have been created and configured correctly on the Hub Transport server
  4. Open Exchange Management Console
  5. Click on the + next to Organization Configuration
  6. Select Hub Transport
  7. Open the Send Connectors tab
  8. Right-click on the existing Send Connector, select Properties and go to the Network tab
  9. Select "Route mail through the following smart hosts:" and click Add
  10. Enter SMARTHOST (you need to use port 587)
  11. If you have more then one Smarthost, repeat the previous two steps

The changes you've made to the Send Connector will take effect straight away without you having to reboot the server or restart any services.

In order to change the port to 587 you will have to issue the following command in the Exchange Powershell Console:

Set-SendConnector -identity "NAME OF CONNECTOR" -Port:587

Afterward restart the transport service and relaying will work

Routing all outgoing mails via the outgoing smarthost with Username Authentication:

A Send Connector must already have been created and configured correctly on the Hub Transport server.

  1. Open Exchange Management Console
  2. Click on the + next to Organization Configuration
  3. Select Hub Transport
  4. Open the Send Connectors tab
  5. Right-click on the existing Send Connector, select Properties and go to the Network tab
  6. Select "Route mail through the following smart hosts:" and click Add
  7. Enter SMARTHOST in the FQDN section
  8. Click Change under the smart-host authentication
  9. Select Basic Authentication
  10. Add your newly created username and password
  11. Click OK

The changes you've made to the Send Connector will take effect straight away without you having to reboot the server or restart any services.

In order to change the port to 587 you will have to issue the following command in the Exchange Powershell Console:

Set-SendConnector -identity "NAME OF CONNECTOR" -Port:587

Afterward restart the transport service and relaying will work

Disclaimer: This documentation may contain references to third party software or websites. N-able has no control over third party software or content and is not responsible for the availability, security, or operation, of any third-party software. If you decide to utilize a release involving third-party software, you do so entirely at your own risk and subject to the applicable third party’s terms and conditions of the use of such software. No information obtained by you from N-able or this documentation shall create any warranty for such software.