"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

Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.

0 comments No comments

155 answers

Sort by: Newest
  1. Anonymous
    2023-09-20T03:57:31+00:00

    Hi - apologies for the delay. I ended up reverting back to the older version of Outlook, we are now back on the new version and it appears that this issue has still not been resolved! I have attached screenshots and hope you get them.

    As others have mentioned, there is no way around this apart from having to shut down Outlook ir go to the OWA and send from the drafts folder there

    PLEASE FIX THIS ISSUE!!!

    Was this answer helpful?

    0 comments No comments
  2. Anonymous
    2023-09-18T07:56:27+00:00

    Same issue. It started happening while I was trying to solve the previous issue of attachments and images being stipped from messages. The KB articles recommended switching to the legacy version. After testing legacy I couldn't bare using it so switched back to new version. Now 50% of my message get permanently stuck like this.

    REALLY FRUSTRATING!!

    Was this answer helpful?

    0 comments No comments
  3. Anonymous
    2023-09-15T11:54:33+00:00

    Having the same issue on multiple Macs, all running latest OS (13.5.2) and after updating to the September patch release of Outlook for Mac using the New Outlook client (16.77 23091003), except that the consistent behaviour for us is the red error box "Message failed to send" appears and the email is stuck in Outbox (and not in drafts).

    When the email is stuck in Outbox we see similar behaviour; cannot resume editing, cannot send but also cannot delete. The error message when you try is that the email is open in another instance (which is not the case).

    However, if we then open OWA, the stuck email is in the Drafts folder and you can immediately click Send and it works.

    I can also confirm that revert to legacy Outlook does not encounter the same problem.

    Was this answer helpful?

    0 comments No comments
  4. Anonymous
    2023-09-14T10:49:26+00:00

    I have exactly the same issue, as do multiple of my colleagues.

    • We all use New Outlook (currently version 16.77)
    • OS is updated to newest version (Ventura 13.5.2)
    • I've tried from multiple profiles

    I've tried attaching picture, but it just says "File(s) failed to upload", so I uploaded the screenshot here: https://snipboard.io/Mk5VpO.jpg

    Is there anywhere a log can be fetched?

    Was this answer helpful?

    0 comments No comments
  5. Anonymous
    2023-08-14T08:49:00+00:00

    Hi David,

    Thank you for visiting Microsoft Community, we are glad to be of your assist.

    As per your description shared, we understand you are encounterring email sending issue in Outlook for Mac, however, we do not see your screenshot thus, to provide possible solution, kindly collect below information for us, thanks in advance:

    Hope above is helpful and we looking forward your update, thank you for your time.

    Regards,

    Microsoft Community

    Was this answer helpful?

    0 comments No comments