Relevant Products: Exclaimer Cloud - Signatures for Office 365
If you use Exclaimer Cloud in a hybrid environment with centralized mail flow, you may find that emails do not route as expected and either of the following scenarios occur:
- Emails route out to the internet instead of using the hybrid connector after being routed back from Exclaimer Cloud.
- Emails do not route to Exclaimer Cloud to have signatures applied; instead, they are routed to On Premises.
Currently, the hybrid send connector is set to apply to all messages at the connector level, and commonly appears similar to the following connector:
The objective of this solution is to modify the connector set up so that it uses a Transport Rule with a lower priority than the Exclaimer Transport Rule; therefore, ensuring that signatures are applied before messages are routed On Premises.
Please follow the steps below to reconfigure the hybrid send connector:
- Reconfigure the hybrid send connector
- Add a new mail flow rule
- Configure the new mail flow rule
- Add your .onmicrosoft address to the Exclaimer portal
Reconfigure the hybrid send connector
- Log on to the Office 365 Portal as a Global Administrator.
- Open the admin center.
- Click admin centers and select Exchange.
- Select mail flow then connectors.
- Reconfigure the hybrid send connector to apply Only when I have a transport rule set up that redirects messages to this connector:
- Leave all other connector settings as they are and save the connector.
Add a new mail flow rule
- In the admin center under mail flow, select rules.
- Click the + (plus) button to add a new rule.
- Give the rule a name - for example: Send on-premise.
Configure the new mail flow rule
- Scroll down and click More options to enable additional rule options.
- Add a condition which states The sender is located inside the organization. This will ensure that all emails sent from your Office 365 tenancy are routed through the connector.
- Add an action which states Redirect messages to the following connector and select your Hybrid Send Connector. The rule will resemble the example below:
- Add an action using the options Modify the message properties and Set a Message header.
- Set the message header to something, such as 'x-sentonpremise' and Value to 'True'.
- Add an exception for 'A Message Header' that 'Matches these text patterns' and set that rule to also be for the text 'x-sentonpremise' and Value to 'True'.
This combination of adding the header and setting it as an exception means that if the mail is returned to your Office 365, it will not be redirected to the connector again, and this will prevent mail loops.
- Click Save to save the new rule. It will now be shown in the rules list with a priority of 1. You will also now see an Exclaimer rule called Identify messages to send to Exclaimer Cloud, which has a priority of 0.
Your Office 365 set up is now complete.
Add your .onmicrosoft address to the Exclaimer portal
The final step of this process is to return to the Exclaimer Cloud portal to ensure that emails are routed to Office 365 once the signature has been applied:
- Log in to your Exclaimer portal.
- Select Launch for your subscription.
- Select Settings in the Cloud portal.
- Select Mail Flow.
- Under Mail Routing.
- Select Static domain.
- Enter your .onmicrosoft address (listed in your Office 365 tenancy under Domain Name):
- Click Save to save the changes.
Your setup is now complete.