Delivery failure for emails sent from my hotmail personal email account.

Question

This has been very frustrating. I have answers to deliver at a very urgent basis and I get this message.

I have been sending emails to my contacts for ages and never faced this weird issue. Out of nowhere I receive this delivery failure message.

Delivery has failed to these recipients or groups:

[B B] Your message wasn't delivered because the recipient's email provider rejected it.

There is urgent response that I need to send, but I can't. Extremely disappointed with this inconvenience.

Can this be fixed at the soonest.

Answer 1

Hello

Is that the complete bounce back message you received ? It is very generic error and didn't specify the specific reason. If there's more info to that bounce back, please do share.

Otherwise, try this:

Can you use the instruction here, change the email to plain text or rich text format (basically avoid the html format) and see if it goes through:

https://support.microsoft.com/office/change-the-message-format-to-html-rich-text-format-or-plain-text-in-outlook-338a389d-11da-47fe-b693-cf41f792fefa

Answer 2

Hi Vinay Rao,

Thank you for reaching out to Microsoft Q&A forum.

I am sorry for the inconvenience, especially since your email is urgent. The non‑delivery report (NDR) indicates that the recipient’s email system is rejecting the message.

Please try the steps below to troubleshoot:

• Double‑check the recipient’s email address (including the domain) to ensure there are no typos.
• Try sending the same message from Outlook on the web (outlook.live.com). If possible, resend it as a plain‑text email and temporarily remove attachments or links to rule out content being filtered.
• If you are sending to a group or a specific email provider, please ask the recipient (or their email administrator) to whitelist your Hotmail/Outlook.com address or domain, as the recipient side may be blocking or filtering connections from the sending server.

If the incident persists, please forward the full non-delivery report (including the 550 / 5.x.x code) via Private Message so I can review it further. This will help determine whether the message is being blocked by recipient-side policies or whether the sending account is temporarily restricted, for example if the system has detected activity that resembles spam.

Please feel free to let me know if you have any further updates, thanks

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Answer 3

The answer is not accepted as I have tried everything that was suggested and still facing this issue. I want realtime solution not AI solution, please!!