Regarding delays in receiving emails on Exchange Server

Question

[Note] This sentence was translated from Japanese to English using Google Translate.

For some reason, I would like to use two on-premises Exchange Servers, but as shown in the ExchangeECP delivery report results below, there will be a delay in reception.

[6 minute delay report] Sent at 16:54 → Received at 17:00

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Delivery report

Information System Department (Information System Address@*************)‎

On hold

2024/04/13 16:54 <ExchangeServer A FQDN>

<ExchangeServer A FQDN> received a message from <ExchangeServer A FQDN>*PC name is uppercase.

2024/04/13 16:54 <ExchangeServer A FQDN>

The email address of the recipient "Information system address @************" is the email address

Updated to "Information system address@*************". The message is being delivered.

2024/04/13 16:54 <ExchangeServer A FQDN>

Messages are from 2024/04/13 16:54:18 (UTC+09:00) Osaka, Sapporo, Tokyo,

Queued on server '<ExchangeServer A FQDN>'.

The time of the last attempt to send a message was 2024/04/13 16:55:13 (UTC+09:00)

Osaka, Sapporo, Tokyo, the error generated is '[{LED=};{MSG=};{FQDN=};{IP=};{LRT=}]'.

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[No delay report] Sent at 16:39 → Received at 16:39

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Delivery report

Information System Department ‎(Information System Address@***************)‎

On hold

2024/04/13 16:39 <ExchangeServer A FQDN>

Message from <ExchangeServer A FQDN> to <ExchangeServer B FQDN>=421 4.2.1 Unable to connect ->

SocketError: Failed to connect. Winsock error code: 10051, Win32 error code: 10051;Redirected to <ExchangeServer B FQDN>.

2024/04/13 17:05 <ExchangeServer A FQDN>

There are no further logs, so no further information is available about this message.

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The sender and recipient are the same in both cases.

Also, in the delay report, for some reason, his FQDN for Exchange Server A was written in lowercase letters only in one place.

The OS of each Exchange Server is shown below.

ExchangeServer A: Windows Server 2016 std/Exchange Server 2016

ExchangeServer B: Windows Server 2022 std/Exchange Server 2019

We look forward to hearing from you, no matter how trivial.

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Answer 1

Thanks for posting your question in the Microsoft Q&A forum.

The delay in email delivery could be due to network connectivity issues between the two Exchange Servers. The "Unable to connect" error message and the Winsock error code 10051 (which indicates a network-related error) suggest that there might be a problem with the network connection between the servers.

• Check the network configuration, firewall settings, and any network devices (routers, switches, etc.) between the two Exchange Servers to ensure proper connectivity.
• Verify that the servers can ping each other and that there are no network-related issues.
• Review the Exchange Server event logs for any relevant error messages or warnings that might provide more insights into the problem.

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