Hi @DCS CUSTOMS ，
Do you mean that only email from specific senders will be delay? Or it happens randomly to all senders?
Did you change any setting of Exchange server before this issue occurred?
How long will the mail be delayed?
I click the link you provided, and it will be redirected to a third-party website, I can’t get more information.
1.When you received the delay email, you could analyze the email headers through ExRCA, and the results will show the specific delays. We can see if the delay occurred before or after reaching Exchange.
Message Header Analyzer: mha.azurewebsites.net
2.You could run the following command to check the process and time of mail transmission in Exchange server.
Get-MessageTrackingLog -Start "<>" -End "<>" -Sender "<>" -MessageSubject <>
For more information: Get-MessageTrackingLog
In addition, Exchange Server 2010 reached its end of support on October 13, 2020. Please upgrade the Exchange server to a higher version as soon as possible.
For more information: Exchange 2010 end of support roadmap
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