Article ID: 976108 - View products that this article applies to.
Microsoft Exchange Server 2007 introduced that the Edge Transport server role can use the hosts file for name resolution to the Hub Transport server role. However, messages from an external server to a Hub Transport server may be queued on an Edge Transport server. Additionally, if you open the Queue Viewer from the Exchange Management Console, you find that the status of the queued messages are "451 4.4.0 DNS Query Failed" . This problem occurs when the following conditions are true:
This problem occurs because Exchange Server 2007 does not check the hosts file if the Edge Transport server has no DNS server configured.
To resolve this problem, install the following update rollup:
(https://support.microsoft.com/kb/979784/ )Description of Update Rollup 3 for Exchange Server 2007 Service Pack 2
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about how to configure DNS settings for Exchange 2007 Servers, visit the following Microsoft Web site:
Configuring DNS settings for Exchange 2007 Servers
For more information about how to configure Edge Transport Server connectors, visit the following Microsoft Web site:
Configuring Edge Transport Server Connectors
Article ID: 976108 - Last Review: March 18, 2010 - Revision: 1.0