Reports can also be received from remote systems. The routing process for reports is the same as for messages and probes, regardless of the report's origin, except when the report is destined for a distribution list.
Microsoft Exchange Server generates the following reports:
When the report destination is a distribution list, the MTA backtracks through Originator_ and DL_Expansion_History to find the originator of the message. Each O/R name found by this recursive process in turn becomes the next report destination and is passed back through the routing process. If the previous entry in this list was a distribution list, the process is repeated until the actual originator is found.