I cannot find an email that I sent, with an attachment. That email shows up in the thread of the response to it, so I know it was sent and received, but I can't find the email in my Sent folder, or it's attachment.
Do you mean loss of emails with attachments or disappearance of attachments in emails?
Does Outlook web have the same problem?
Please try searching for the email on the local client, and if the search is found, hover over the search result to display the directory where the email is stored.
Also, I checked a known issue in Microsoft 365 admin center Service health where some users' emails with attachments sent from Outlook for Mac may be delivered without attachments. You can contact your administrator to see the latest status of this issue. More information, see: EX637339.
Hope this helps!
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