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Hi
We are having trouble with one of our user sending meeting request to client EXTERNAL email through Office 365.
It seems to have started yesterday.
What does the errors mean and how to solve it?
Reason: [{LED=};{MSG=};{FQDN=};{IP=};{LRT=}]
Currently in our Company, we are running a hybrid Office 365 setup, few users are on Exchange-On-premises and others are on Office 365.
The email has been running fairly smooth, however there is a problem that arose which is delay NDR bounce back in sending meeting request mail from the Office 365 to EXTERNAL.
While checking at protection.outlook.com, the message trace shows a delay/defer with the following message:-
Reason: Reason: [{LED=};{MSG=};{FQDN=};{IP=};{LRT=}]
Could anyone know the possible reason for this delay?
Regards,
Syed Naveed
Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Answer accepted by question author
Hi Syed,
If you have further updates on this issue, feel free to let me know.
Regards,
Marvin
Hello Marvin,
Thank you for your support clarification and information.
I'll update this records and let you know the results, And yes A record is pointing to our On-prem exchange server.
Thank you.
Regards,
Syed Naveed
Hi Syed,
Thank you for the detailed clarification and information. According to the error code 550 4.4.7, it indicates that the recipient email server failed to accept the message due to the network connection issue or anti-spam settings. For your reference, see Fix email delivery issues for error code 550 4.4.7 in Exchange Online.
However further looking into the message header, I found that the SPF authentication result is none, which indicates that the domain does not have an SPF record or the SPF record does not evaluate to a result.
(your domain info has been wiped out)
Generally, if the email is successfully delivered to the recipient side, the SPF authentication result will be "pass", and the sender IP will appear. So in my view, the recipient email server could fail to authenticate the SPF record and keep rejecting the email.
In this scenario, before you check the other solutions in the article, please first check if the SPF record is configured correctly. Of course, you can also add the sender IP to the SPF record to check if it helps.
Regards,
Marvin
Hello Marvin,
Thank you for your response to this matter,
Re-to your queries have send you all the details, please check your private message.
Thank you.
Regards,
Syed.
Hi Syed,
From the image, we can see that Exchange server has received this email but it's still processing to delivering this email. However currently we cannot determine the root cause. It could be that the recipient email server rejected to receive this email, or somehow the Exchange server cannot send the email out but keeps trying in the queue.
If it happens to only one user in your organization, you can ask the user to send another meeting request to check if the issue persists. Besides, if the other users who use the same domain send the meeting request, will the issue recur?
For the further analysis, we'd like to collect more information to better understand this issue.
Regards,
Marvin