Using New Outlook on Windows for professional communication and productivity
The behavior described is not documented in the provided material as a known or expected feature of Outlook, and there is no official fix or configuration-based workaround for New Outlook in this context.
The available documentation only covers:
- How Outlook normally handles Sent Items (including IMAP duplication and how to disable local saving of sent items in classic Outlook for Windows).
- How to ensure sent items are saved at all (via the Save copies of messages in Sent Items folder option and related Group Policy/registry settings in classic Outlook).
- How to view and troubleshoot missing Sent Items in classic Outlook.
- Registry-based behaviors for delegates and shared mailboxes (Deleted Items and Sent Items) in classic Outlook.
None of these address New Outlook for Windows deleting a sent message when a leftover draft is deleted, and none describe a setting that would change or prevent this behavior in New Outlook.
Because of this, the issue must be treated as an application defect rather than a configuration problem based on the available information. The only supported next step indicated by the documentation is to open a support case with Microsoft so the issue can be investigated and tracked as a bug at the service or client level.
Until Microsoft provides a fix, the only safe operational workaround implied by the documentation is procedural: do not delete the leftover draft copies if the corresponding sent messages must be retained, and instead rely on the Sent Items folder for record-keeping.
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