We are using Exchange 2007. We have a messaage size restriction on both our send and recieve connectors. We also have a Transport Rule in place which limits the size of attachments. The transport rule specifies that a "5.7.1 Delivery not authorised" message be sent to all senders who attempt to send an oversized attachment. Although the failure notification is sent to internal message senders none are sent to external senders. How do I configure exchange to send failure notifications to external senders of oversized messages?

Hello, How your mailflow works? Do you have Edge Transport Server or Hub Transport accepts messages from internet? Please post your transport rules configuration here to further troubleshooting. I think you need to set two transport rules one for mails are coming inside org and one for going outside to the organization. You can also set Global/Organizational message size limit. References: Exchange 2007 - Message SizeLimits Managing Message Size Limits

please also check this. Organzation Configuration->Hub Transport-Remore domains->right click"default domain(*)"->format of orignal message sent as attachment tojounal report->check "allow non-delivery reports". although it is checked by default, I still suggest you confirm it in case you ever modified it ago. -Jason

We are not running an Edge Transport server only a hub transport server. There is only one Exchange server and all the roles are delegated to it. The "allow non-delivery reports" is checked. I seemed to have solved the problem by disabling the hub transport rule that I had set with regards to maximum attachment size (Org Config, Hub Transport, Transport Rules) and returning the send connector (Org Config, Hub Transport, Send Connector) and the Receive Connector (Server Config, Hub Transport, Receive Connectors) back to their defaults. I then went to Transport Settings (Org Config, Hub Transport, Global Settings) and set the maximum send and receive limits from there. I don't quite understand the logic behind it but all senders are now getting a failure notice if they send an oversized message