Sending, receiving, and organizing email in Outlook.com
Try these Outlook.com steps first, because the folders may be hidden rather than deleted:
- Sign out of Outlook.com.
- Clear the browser cache.
- Close all browser tabs and windows.
- Sign in again.
If the left folder pane is still missing:
- Maximize the browser window or scroll left.
- Select the three-line icon in the left sidebar to show or hide folders.
If folders were recently renamed or created and then disappeared, items from those folders can still be found by using search, and that issue is fixed in the new Outlook.com.
If a folder was deleted, check Deleted Items:
- In the left pane, expand Deleted Items by selecting the arrow next to it.
- Look for the missing folder or messages there.
If the problem is only in Outlook on the web and some folders are missing, one possible cause is too many folders in the mailbox. Outlook on the web can display up to 10,000 folders at one time.
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