Exchange 2010 Error 451 4.4.0
Availability Migration You are here: Home / Solutions / Messages Queuing with Error 451 4.4.0 DNS Query FailedMessages Queuing with Error 451 4.4.0 DNS Query Failed October 16, 2014 by Paul Cunningham 42 Comments I recently encountered an Exchange 2010 server that was unable to send emails to a small number of domains. The messages would queue on the outbound transport server, and a look at the queue status would return an error of "451 4.4.0 DNS query failed". Interestingly the domain name was resolving just fine in DNS when queried from the server, including for MX record lookups, and a telnet to port 25 was successful too. When I created a send connector just for that namespace and designated their MX as the smart host IP address delivery was successful. It just would not work if DNS lookups were being used. There are many reports of this error on forums such as TechNet but no concrete explanations for the causes or how to solve it. I saw many references to disabling IPv6 on the server, but also follow up reports that this did not work. In the end the solution was to enable the option to force the send connector to use the external DNS settings for the transport server. Even though there was nothing unusual about the external DNS settings on that server. They were simply set to use the DNS settings of the network interface, which worked fine for NSLookup. After changing the send connector config and restarting the MSExchangeTransport service the mail delivered successfully to the troublesome domains. It's possible this is a bug with the particular combination of Exchange 2010 and Windows Server 2008 R2 that the customer is running, although I could not find anything that specifically confirms this. It is also not an issue I've encountered elsewhere with this combination of server versions, nor can I reproduce it in a test lab. But if you do encounter this issue the above solution seems to work fine and is certainly very quick and easy to try. Solutions About Paul CunninghamPaul is a Microsoft MVP for Office Servers and Services, specializing in Exchange Server and Office 365, and is the publisher of Exchange Server Pro. He lives in Brisbane, Australia, and works as a consultant, writer and trainer. Find Paul on Twitter, LinkedIn, or Facebook. Comments Skip McCurdy says October 30, 2014 at 9:58 pm We had the exact same issue here with no reason for it. We did the same thing and it worked for us a
Выбрать другой язык можно в списке ниже. Learn more You're viewing YouTube in Russian. You can change this preference below. Закрыть Да, сохранить Отменить Закрыть Это видео недоступно. Очередь просмотраОчередьОчередь просмотраОчередь Удалить всеОтключить Загрузка... Очередь просмотра Очередь __count__/__total__ Microsoft Exchange Server Error 451 4.4.0 DNS Query Failed EmailDoctor ПодписатьсяПодписка оформленаОтменить подписку44 Загрузка... Загрузка... Обработка... Добавить в Хотите сохраните это видео? Войдите в аккаунт и добавьте его в плейлист. Войти Поделиться http://exchangeserverpro.com/messages-queuing-error-451-4-4-0-dns-query-failed/ Ещё Пожаловаться Пожаловаться на видео? Выполните вход, чтобы сообщить о неприемлемом контенте. Войти Текст видео Статистика 1 445 просмотров 3 Понравилось? Войдите в аккаунт, чтобы поставить отметку. Войти 4 0 Не понравилось? Войдите в аккаунт, чтобы поставить отметку. Войти 1 Загрузка... Загрузка... Текст видео https://www.youtube.com/watch?v=hzxxuTHGZqI Не удалось загрузить интерактивные субтитры. Загрузка... Загрузка... Оценка становится доступна после аренды видео- В данный момент эта функция недоступна. Повторите попытку позже. Опубликовано: 28 мар. 2016 г.Fix exchange server error 451 4.4.0 dns query failed. exchange 2010 dns lookup failed error resolution. http://goo.gl/Xz41h4Know cause and symptoms to the error. The prerequisites for easy resolve and if it fails then go for the solution. Manage Edge Transport server role to resolve the error. This is also the solution of some following errors: - Exchange 2010 Error 451 4.4.0 DNS Query Failed- Exchange 2013 Error 451 4.4.0 DNS Query Failed- exchange 2013 queue 451 4.4.0 dns query failed- 451 4.4.0 dns query failed exchange 2010 hub transport Категория Наука и техника Лицензия Стандартная лицензия YouTube Ещё Свернуть Загрузка... Автовоспроизведение Ес
Message Queued with 451 4.4.0 Dns query failed We discussed this error earlier here http://msexchangeguru.com/2013/11/23/451-4-4-0-dns-query-failed-the-error-was-smtpsend-dns-nonexistentdomain-nonexistent-domain/ We also know this issue can come because of http://msexchangeguru.com/2014/11/14/e2010451-4-4-0-dns-query-failed/ multiple reasons. So today I discovered another fix so I am sharing here. Infra: This infrastructure has windows 2012 R2 domain controllers with AD integrated DNS on it. We are https://kx.cloudingenium.com/microsoft/exchange-edge-2010-451-4-4-0-dns-query-failed/ migrating from Exchange 2007 to Exchange 2010. This is customer choice, I would have chosen Exchange 2013. Mixed mode with Exchange 2007 and windows 2008 non R2 DCs. Issue: Until exchange 2010 migration everything was working fine. Post cut over we got few secure domains had Message Queue with 451 4.4.0 DNS Query failed Troubleshooting: Did the nslookup and look for the mx record. Mx record was present and telnet to this record was working. This means DNS Query was working. I created the send connector and pointed to one of the MX exchange 2010 error record hostname. Restart the transport service on all exchange 2010 servers But still the messages were queued up with the same error. Resolution: Turn off the EDNS0 feature on Windows-based DNS servers. To do this, take the following action: Open the command prompt with run as administrator, Type the following command, and then press Enter: dnscmd /config /enableednsprobes 0 Did the same on all domain controllers. Selected the message to retry or restart transport fixed my issue. Root cause: This issue occurs because of the Extension Mechanisms for DNS (EDNS0) functionality that is supported in Windows Server DNS. EDNS0 allows larger User Datagram Protocol (UDP) packet sizes. However, some firewall programs may not allow UDP packets that are larger than 512 bytes. Therefore, these DNS packets may be blocked by the firewall. Reference: http://support.microsoft.com/kb/832223 This applies to domain controllers post windows 2008 R2 and above which is why windows 2008 non R2 domain controllers were working fine. Prabhat Nigam Microsoft
» Feb 25 Exchange Edge 2010: 451 4.4.0 DNS query failed Categories: Exchange, Exchange 2010, Microsoft, Servers by Juan Carlos What causes 451 4.4.0 DNS query failed on Exchange Server 2010? After installing Microsoft Exchange Server 2010 Edge and subscribing to it all my emails were hanging on the queue and not being delivered to the hub server. I had all my network cards set up with my DNS server so I wash´t expecting any issues but I kept seeing the 451 4.4.0 DNS query failed message. My first approach to solving this was to understand what DNS query was the one failing. While looking at the different settings I stumbled when I saw the smart host being "- -". First I thought it was a typo and then I assumed the DNS was failing as it could not resolve that address. It turns out "- -" actually means the subscribed hub address so it automatically provides the correct hub address for you. Still confused as to what 451 4.4.0 DNS query failed meant so the next stop was the DNS resolution settings on the Exchange Edge server. If you go to the properties of your Exchange Edge server you'll see a tab that reads "Internal DNS". Here the default setting was to use the network card's DNS automatically. I assumed that would work as the network card did have my internal DNS configured (which resolves outside addresses as well). It happens that for some reason that was not working. The solution Go into the properties of the Edge server and for the Internal DNS instead of using my network cards simply type in the address of the internal DNS and voila! That fixed it. For some reason is using not your internal DNS server (if you happen to have multiple set up) so it cannot resolve the hub transport address correctly. As simple as that. For more information and troubleshooting steps if adding your internal DNS Server does´t work check out: Troubleshooting Mail Queues That Are Increasin