"Message failed to send" Red Error box in Outlook 365 for Mac

Anonymous
2023-08-14T06:11:51+00:00

Hi everyone - has anyone had issues with sending emails using Outlook 365 for Macs? Especially a red error box that appears at the bottom (attached) and says "Message failed to send Open" The email is then stuck in drafts with the option to continue editing but it is simply frozen in drafts and the only way is to delete and try again. Alternatively, you can go to the webmail version of outlook, find the drafts folder and send from there. This has been happening on/off for several weeks now, no pattern, just happens occasionally.

This version of Outlook 365 is absolutely **** with so many issues

Outlook | MacOS | Legacy Outlook for Mac | For home

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  1. Anonymous
    2024-02-14T15:23:24+00:00

    I go directly to my Outlook Mobile app, Drafts, and hit send. It goes every time.

    It's very annoying that Microsoft has yet to address this problem.
    It happens in both the legacy and new UI.
    It happens on emails with no attachments and attachments.

    It's random and annoying as heck.

    As of today, I'm running Outlook 16.82 and MacOS Sanoma 14.3.1 on an O365 business account.

    To give this more attention, I can confirm the exact same issue with the Ventura 13.5.2, New Outlook Version 16.77.1 (23091703) with an O365 business account.

    Some mails go through, some don't. Sometimes it helps just deleting the mail in the Outbox, type the new one, send again. So for me it's impossible to find the actual cause.

    Side note: If you have S/MIME enabled, you can't even go to OWA and send the mail. You HAVE TO delete it and type it again / paste the copied text.

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  2. Anonymous
    2024-02-26T17:01:09+00:00

    Any fix for this yet? The "Message failed to send Open" has been happening to me for a few weeks now. Also, unable to cancel sending and re-edit. If I resume editing, it sends the message half way through my editing the email! Version 16.82.1.

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  3. Anonymous
    2024-02-26T17:08:28+00:00

    For me it seems fixed just by doing nothing.

    Outlook v16.82.1

    Sonoma 14.3.1

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  4. Anonymous
    2024-02-26T23:34:44+00:00

    My outlook was working fine this morning, then suddenly stopped receiving/sending and I get the message that the email was not sent. I noticed there was a system update - so I did that and restarted... still not working. Super frustrating! Any idea how to resolve this? My picture wont upload.... it is V. 16.82.1

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  5. Anonymous
    2024-02-27T04:24:57+00:00

    Not for me - this is so f******d!! Been almost 12 months and still no fix!

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