Updating destination list delivery server has failed
5.1.1 is the most common Exchange 2010 NDR; there is a problem with the recipient address. Possibly the user was moved to another server in Active Directory. Maybe an Outlook client replied to a message while offline. For example, when trying to send an email to [email protected] Most likely, a distribution list or group is trying to send an email. The application event log may have an Event ID 6025 or 6026, which has more detailed information.
Tricky looping problem, a contact has the same email address as an Active Directory user.
However, I have discovered a few useful patterns, for instance, 5.1.x indicates a problem with the email address, as opposed to server or connection problem.
In addition, 5.2.x means that the email is too big, therefore I recommend checking the message limit setting on your Exchange 2010 server.
If your mail queues are getting full of NDRs from the postmaster to possible spammers, then disable 'Allow delivery reports' on the Property sheet: Hub Transport\Remote Domains\Default Properties\Allow delivery reports.
Your message did not reach some or all of the intended recipients.
Perhaps an anonymous user is trying to send mail to a distribution list. It could be that the sender cannot send to the alternative address.
- Properties - Mail Flow Settings - Message delivery restrictions. Instead allow only standard authorization on the SMTP receiver on the Exchange 2010 server. On another tack, check external IP address of ISA server. Solar Winds' Config Generator is a free tool, which puts you in charge of controlling changes to network routers and other SNMP devices.
Occasionally, you get an Exchange NDR beginning with 4, in which case there is hope, the email may get through eventually.
NDR codes such as 5.5.0, or 4.3.1, may remind you of SMTP errors 550 and 431.