For Outlook.com, check these in order:
- Set the message list filter to All.
If a filter is active, newer messages may be hidden.
- Check the Other tab if Focused Inbox is enabled.
Messages may be landing there instead of Focused. If found there, move them back to Focused inbox.
- Check these folders for the missing mail:
- Junk Email
- Deleted Items
- Archive
If a message is in Deleted Items, restore it. If it is no longer there, use Recover items deleted from this folder on a computer. Messages removed from Deleted Items are recoverable for 30 days.
- Review Rules and Sweep settings.
A rule may be moving messages out of the Inbox. Open Rules settings and remove or edit any rule that incorrectly moves mail.
- Check recent sign-in activity for the Microsoft account.
If there was unusual activity, review the recent activity page and secure the account.
- If this issue is only in Outlook desktop Cached Mode, but the messages are visible in Outlook on the web, the messages may be stuck in the incoming item processing pipeline. In that case:
- Close Outlook.
- Run
Outlook.exe /cleanips
- If that does not help, in Outlook: right-click Inbox > Properties > General > Clear Offline Items, confirm removal from the
.ost, then select the Inbox and press Shift+F9 to resynchronize.
If the missing messages started after a specific date, these checks help determine whether the mail is being filtered, moved, deleted, archived, or only hidden in a cached Outlook profile.
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