Exchange e-mails delayed/not delivered to *Internal* Distribution List

exchangeexchange-2007

I'm having an issue right now with a specific distribution list on our Exchange 2007 server. Sending e-mails to it causes exchange to bounce back after several hours with "Delivery is delayed to these recipients or distribution lists: ". No recipients receive the message and it's an internal distribution list. Does anybody know why this could be happening?

It's the second time it's happened, the first time was a couple of months ago.. That time we opened a support case with Microsoft as we were so confused by it…. but never really figured out the exact root cause or why it started working again.

One weird thing I noticed is that despite the fact that Exchange will notify the sender after four hours that the message is delayed… the message does not appear in the Queue viewer

Best Answer

I didn't realize there was another Hub transport server involved in this organization. After looking at the Queue in that Hub transport server, I found the delayed messages, which they were trying to send to the main server. In the queue viewer it showed the error it was recieving... "'451 4.4.0 Primary target IP address responded with: "451 5.7.3 Cannot achieve Exchange Server authentication." Attempted failover to alternate host, but that did not succeed. Either there are no alternate hosts, or delivery failed to all alternate hosts." A bit of googling led me this solution, which I've pasted below

Change the Default receive connector properties to the following

Authentication Tab:
TLS(Transport Layer Security): Select
Basic Authentication: Select
Exchange Server Authentication: Select
Windows Integrated Authentication: Select
External Security (IPSec): not selected

Permission Groups:
Anonymous Users: Uncheck
Exchange Users: Select
Exchange Servers: Select
Legacy Exchange Server: Select
Partners: Uncheck