A client of mine sent out a mass email to a bunch of people on his contact list. A bounceback email was received by my client stating that: "The server has tried to deliver this message, without success, and has stopped trying. Please try sending this message again. If the problem continues, contact your helpdesk."
That error is associated with every recipient in that mass email. Any ideas on where to look to resolve this? He is able to send and recieve other emails normally.
Go to System Manager | Global Settings | Message Delivery | Defaults Tab
Check all your defaults here and make sure they are setting correctly. We had similar issue sending to a large list - Exchange had 100 outgoing recipeints as the maximum.
Good luck.
How is he sending the message? To an address that he thinks is an alias and isn't? Is the bounceback from individuals in the list or from some alias user that doesn't exist and is supposed to be expanded into a list of users?