"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
    2024-05-23T08:57:51+00:00

    Updated Outlook to the latest and it seems to have been fixed for now!

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  2. Anonymous
    2024-05-28T22:41:47+00:00

    Running the latest 16.85.1 and still received the dreaded message in a red box "Message Failed to Send". It's not every email, its's occasional and seemingly when I reply to an email chain, that has embedded images (from signatures) being shown as attachments, (although I will watch this more closely).

    If I delete the attachments (on the failed email), it still will not send. I can do this over and over with the same email. It will fail.

    If I take the original email chain I replied to, and remove all the attachments first and then send - it will work

    If I take the same email chain and start/create a new email where I simply paste the entire contents of the failed email, but none of the attachments, it also then sends.

    Almost as though once it decides it does not like the email, there is nothing you can do to make it send.

    As many have said this is a new phenomenon and I have now run into issues, because of an email I was 'supposed' to send that I did not, only to find it in my drafts and for a while, blaming myself for not hitting send, until I realized that I did hit send, but it actually will not send.

    Now I have to check upon sending email that the 'red box' doesn't appear.

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  3. Anonymous
    2024-06-03T11:18:48+00:00

    Yes, removing embedded images works for me too!

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  4. Anonymous
    2024-06-03T13:40:30+00:00

    I tried a few different ideas from various responses. Deleting embedded images didn't work. Deleting everything in the thread, including my signature, worked. But then I tried to just copy my reply and paste to a new reply and that also worked. So it seems totally random what works and what doesn't. Really frustrating in any case and another reason I dislike "New" Outlook (kind of like "New Coke" years ago). Also hate that I can't delete attachments when people send me huge files I don't need to save.

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  5. Anonymous
    2024-06-12T16:07:11+00:00

    I'm baffled why Microsoft hasn't addressed this issue. Because they think it's only affecting a "small group of users"? - they need to realize that only a very small percentage of people will complain or comment on a thread like this. It took me months of having this problem to finally search deeper and discover this thread and learn that I'm "not alone".

    A year seems like plenty of time to resolve this "bug". Work-arounds are not an acceptable answer anymore.

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