Carry out these checks and fixes in Outlook.com and Outlook on the web:
- Check filters
- In the Inbox, select Filter above the message list.
- Change it to All so no messages are hidden by filters like Unread, Flagged, or a date range.
- On mobile apps or a mobile browser, clear any filter shown above the message list.
- Check rules and Sweep
- Go to Rules settings and review Inbox and Sweep rules.
- Disable or delete any rule that moves or deletes messages unexpectedly.
- Check the Archive folder
- Open the Archive folder and look for the missing messages.
- To move a message back, select it and choose Move to > Inbox (or on mobile: … > Move to folder > Inbox).
- Check recent sign-in activity
- If there is any chance the account was accessed by someone else, go to the Recent activity page and review sign-ins for the last 30 days.
- Follow the guidance in What is the Recent activity page? if suspicious activity is found.
- If messages are still missing or Inbox still does not update
- Use Outlook.com’s built-in Help: select Help on the menu bar, describe the problem, then at the bottom choose Still need help? and select Yes to contact support.
- If sign-in is not possible, use the dedicated help link for Outlook.com sign-in issues.
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