A Microsoft application for managing email, calendars, contacts, and tasks across devices and platforms.
Since the messages are missing both on the phone and online, this is not a mobile sync issue. The mailbox itself no longer shows that one-year range.
Based on what was already checked, the next supported steps are:
- Use a computer and search the whole mailbox, not just Inbox. Search by a known sender, subject, or keyword from one of the missing messages, and make sure the search scope is All folders.
- Check these locations again in Outlook.com because messages can be moved unexpectedly:
- Deleted Items
- Recover items deleted from this folder at the top of Deleted Items
- Archive
- Junk Email
- Other tab if Focused Inbox is enabled
- If a missing message is found in Deleted Items, select it and use Restore. On mobile, use Move to folder > Inbox.
- Review account activity if the disappearance was not intentional. Check the Recent activity page for unusual sign-ins from the last 30 days.
If the messages are not in any folder and do not appear under Recover items deleted from this folder, the remaining step is to contact Outlook.com support for mailbox review.
For a work or school Exchange Online mailbox, an administrator can investigate whether the messages were deleted or moved by using Microsoft Purview audit logs and Exchange Online PowerShell. Relevant audit operations include SoftDelete, HardDelete, MoveToDeletedItems, Move, and Update.