this was the error that i found on logs files in C:\Program Files\Microsoft\Exchange Server\V15\TransportRoles\Logs\Hub\Connectivity

2022-10-05T18:26:41.780Z,08DAA6FEDE772E3D,SMTP,site:nombre-predeterminado-primer-sitio; version:14,-,Messages: 0 Bytes: 0 (Retry : Connection dropped due to ConnectionAborted)
2022-10-05T18:27:41.793Z,08DAA6FEDE772E3E,SMTP,site:nombre-predeterminado-primer-sitio; version:14,+,SmtpRelayToMailboxDeliveryGroup 00000000-0000-0000-0000-000000000000;QueueLength=TQ=1;RN=1;.
2022-10-05T18:27:41.793Z,08DAA6FEDE772E3E,SMTP,site:nombre-predeterminado-primer-sitio; version:14,>,server.dominio.com.py[126.10.10.12]
2022-10-05T18:27:41.839Z,08DAA6FEDE772E3E,SMTP,site:nombre-predeterminado-primer-sitio; version:14,>,Established connection to 126.10.10.12
2022-10-05T18:27:41.925Z,08DAA6FEDE772E3E,SMTP,site:nombre-predeterminado-primer-sitio; version:14,-,Messages: 0 Bytes: 0 (Retry : Connection dropped due to ConnectionReset)

I have 2 Exchange 2016 with DAG and four DBs. Incoming SMTP trafiic passed with KEMP.
When I shutdown Exchange2 server, all working fine, when I shutdown Exchange1 server- on Exchange2 queue I see error
Delivery Type: SMTP Delivery to Mailbox
Status: Retry
Last Error: [{LED=451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to connect -> SocketConnectionRefused: Socket error code 10061};{MSG=};{FQDN=testdb1};{IP=ExchangeServer1 IP})

What Can I do?

Best regards

Tom

i have a problem in a brand new test lab. 2019 SERVER DC, and 2016 server exchange server (exchange 2016 cu20) everything is fully patched and no other software on either server.
problem is, i can send mail from owa using the “administrator” account, but the mail is never received, and also in the delivery reports, i get error 400 so i can’t even see what is or is not happening. i had the exact same issue in ex 2019, so i rebuilt the entire lab from bare metal on ex2016. many exchange install videos show the same process i use and mail just works right out of the box. also i did ZERO config / mods to my exchange server aside from setting up one user mailbox.

any help will be most appreciated.

this worked for me, thanks

Thank you. This helped with our Exchange 2010 -> Exchange 2016 migration. Mail was not coming into our 2010 server after redirecting the NAT to the 2016. This enabled mail to be sent over to the not-yet-migrated boxes still on 2010.

I’ve tried to migrate the Mail server (Exchange 2010-Server 2008 R2 Enterprise) from Hyper-V to Vsphare 6.7.0 but the VM powered on and was able to receive email internally/externally, send internally, however, Exchange couldn’t send email externally. I culled the logs and tried a lot of things but couldn’t get mail to send externally. Everything looked fine but mail being sent out seems to disappear into the ether without showing up in the logs. Had to revert to Hyper-V version.

Do I need to stop/start some services or it’s something else?

Can you please help here?

Thanks

Mail flow is fine internally and externally until I migration a test mailbox over to the 2016 Exchange Server.

Mail flow works internally to and from the 2016 mailbox and 2010 mailboxes internally and the 2016 mailbox can send externally. However, the 2016 mailbox cannot receive from an external source. Mails to this mailbox are queued on the 2010 Exchange Server with the SMTP Relay to Active Directory error.

I cannot migrate mailboxes between servers to continue the serer migration until I have resolved this issue.

Any ideas where the issue may be?.

Thanks a lot.

Thanks, that did it for me on exchange 2007 SP3, add Exchange Server Authentication, you also will need to add in the IP address of new servers on the legacy servers to receive from the newer servers, if they are on a different subnet, during co-existence, which my migration was.

Hi Paul,

Do you have a script to re-create the default receive connectors in exchange 2016?
Best regards,
Oscar