Thursday, October 8, 2015

451 4.4.0 dns query failed. the error was dns query failed with error ErrorRetry Exchange 2013

Issue : Exchange 2013, Email stuck in the Queue, error says " 451 4.4.0 dns query failed. the error was dns query failed with error"

Steps
======
get-queue -server "ExchangeHubServerFQDN" | FL Identity, Status, MessageCount, LastError 

Get-TransportServer –Identity 2007Server | FL

Get-TransportServer –Identity 2007Server | FL “External*”,”Internal*”

Resolution -------------------- Set-TransportServer –Identity 2007Server –ExternalDNSServers $null
et-TransportServer 2007Server –InternalDNSAdapterGuid 00000000-0000-0000-0000-000000000000


1. Once in EAC/ECP, navigate to Servers and open the server properties.
2. Click on DNS Lookups.
3. Make sure the Internal and External DNS lookups are set correctly.  The internal and External DNS settings need to match DNS setting on the network card IP configuration. Type the current DNS settings or leave it blank. Blank forces Exchange transport service to use network card DNS setting


 Use get-transportserver "ExchangeserverFQDN" | FL *DNS* to verify your settings.
2. You want to use the set-transportserver command to set it back to all network adapters or change the custom IP Range.
For Example:  You may wish to change the Internal DNS to use all network adapters and not custom by running:
set-transportserver "ExchangeserverFQDN" -InternalDNSProtocolOption Any

OR type the following to set it to Null

Set-transportserver "ExchangeserverFQDN" -InternalDNSServers $null