Forum Discussion
Exchange 2016 hybrid queue stuck
Hello I recently run a Hybrid wizard everything good!
the only thing that I have is a problem in the communication between on prem accounts and exchange online .
when I send a message to a migrated account the server do the transformation is send to a domain365.mail.onmicrosoft.com but this stay stuck in the queue with the error of 451 4.4.0 DNS query failed with error InfoNoRecords.
i tried a few things but nothing works!
1- I set the connector to ask external dns
2- I test nslookup
3 - I force match the nic guide on the transport service from the network connection info
help
Hi José Leonardo Ovalles Jimenez,
the error 451 4.4.0 DNS query failed typically occurs when there’s an issue with the DNS servers or the communication between your on-premises accounts and Exchange Online.
Here are a few steps you can try:Establish Send Connectors for Affected Remote Domains:
This problem may occur if remote DNS servers disregard AAAA queries or provide unexpected responses. To address this, create send connectors for affected remote domains and configure them to utilize the remote domain's email server as a smart host.Verify DNS Server Functionality:
Ensure the DNS server used by Microsoft Exchange Server is functional. Exchange Server typically utilizes the DNS settings of the network adapter for outgoing remote email routing. Resolve any issues with the local DNS server or configure the external DNS server for remote email routing.Configure External DNS Server for Remote Email Routing:
Open the properties page of the Exchange Server hosting the send connector and add the IP address of public DNS servers in the "External DNS lookups" setting. Select the option "Use external DNS lookup settings on servers with transport roles" in the send connector responsible for remote email routing.
3 Replies
Hi José Leonardo Ovalles Jimenez,
the error 451 4.4.0 DNS query failed typically occurs when there’s an issue with the DNS servers or the communication between your on-premises accounts and Exchange Online.
Here are a few steps you can try:Establish Send Connectors for Affected Remote Domains:
This problem may occur if remote DNS servers disregard AAAA queries or provide unexpected responses. To address this, create send connectors for affected remote domains and configure them to utilize the remote domain's email server as a smart host.Verify DNS Server Functionality:
Ensure the DNS server used by Microsoft Exchange Server is functional. Exchange Server typically utilizes the DNS settings of the network adapter for outgoing remote email routing. Resolve any issues with the local DNS server or configure the external DNS server for remote email routing.Configure External DNS Server for Remote Email Routing:
Open the properties page of the Exchange Server hosting the send connector and add the IP address of public DNS servers in the "External DNS lookups" setting. Select the option "Use external DNS lookup settings on servers with transport roles" in the send connector responsible for remote email routing.
Thanks LeonPavesic
It was done througth de first option:
Establish Send Connectors for Affected Remote Domains:
This problem may occur if remote DNS servers disregard AAAA queries or provide unexpected responses. To address this, create send connectors for affected remote domains and configure them to utilize the remote domain's email server as a smart host.
- Hi Thanks for the Answer,
But the thing here is that the problem is with the Accepted Domain created with the Hybrid is not a remote Domail. I mean the domain is mytenant365domain.mail.onmicrosoft.com this domain does not resolve an public IP or MX record.
