Hi experts i am using exchange hybrid environment, i have created a Transport rule on exchange onprem. Apply this rule if : The sender is : firstname.lastname@example.org and subject includes : XYZ Do the following: Add these recipients to the To box.. Here in the receipients i have add a onprem distribution group(Onpremgroup@mydomain.com) which has the delivery setting to send email inside the organization.
When this rule is triggered i am getting the error Delivery has failed to these recipients or groups: Onpremgroup@mydomain.com Your message couldn't be delivered because delivery to this group is restricted to authenticated senders.
Manually the user is able to send emails to this group but he is getting error when this rule is being triggered
My first guess would be the External Recipients to deliver to this group.
The other thought is why this rule is on the On-prem server when the user sending the email is Cloud. Not sure of your hybrid/mail flow settings, but in my head, the email will only "hit" the rule if the Cloud user is sending to a on-prem recipient.