"Deliverey has failed to these recipients or groups"

Carl MICHEL 1 Reputation point

Good morning,

When I send an e-mail on Outlook, here what I receive :
"Your message couldn't be delivered because you weren't recognized as a valid sender. The most common reason for this is that your email address is suspected of sending spam and it's no longer allowed to send email. Contact your email admin for assistance."

I have never changed the settings and never spammed everyone. It is very annoying because I am a student and I it is thus very important for me to contact my school and teachers... Hope you can find a solution to my problem.


Outlook Management
Outlook Management
Outlook: A family of Microsoft email and calendar products.Management: The act or process of organizing, handling, directing or controlling something.
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  1. Jade Liang-MSFT 9,956 Reputation points Microsoft Employee

    Hi @Carl MICHEL ,

    When I send an e-mail on Outlook, here what I receive :

    What's the type of your account(POP, IMAP or Exchange)?
    In order to further confirm if your issue is related to your account, it's suggested to log in your web mail to check if you could send message normally there. If the issue could be reproduced on your web mail, it may be more related to your account itself instead of Outlook.

    I have researched a lot for your error and found it may occur when your account is blocked in your organization. If your are using a Micorosoft 365 account in your organization, it's suggested to contact your admin directly to check if your account is in the blocked list on server, for more detailed information, you could refer to this article: Remove blocked users from the Restricted Users portal in Office 365

    Hope that would be helpful to you, and if that's not your case or you still need further assistance, please feel free to post back.

    If the response is helpful, please click "Accept Answer" and upvote it.
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