"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
    2023-09-25T15:07:16+00:00

    same here.

    Outlook Version 16.77

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  2. Anonymous
    2023-09-21T11:14:08+00:00

    Nothing changed on my side. If anything, then it got worse today. Could send one out of 20, maybe.

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  3. Anonymous
    2023-09-21T10:42:02+00:00

    50+ emails sent today with zero failures. I'm not aware of any changes I've made to fix the problem. All current settings in Outlook are back to how they were when problem started.

    Has problem been solved for you?

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  4. Anonymous
    2023-09-20T23:21:39+00:00

    OK so today my Outlook is working perfectly, it's not stripping images or attachments. I did nothing different from yesterday when 50% was having the "Resume editing" hang. Very strange. One thing I did notice however is that in the past 10 hours i've had 50+ spam emails getting through to my inbox. This never happens. I wonder if MS are doing something in backend around email flow to try solve this. I'll update again if messages break again.

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  5. Anonymous
    2023-09-20T08:50:01+00:00

    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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