Sending, receiving, and organizing email in Outlook.com
I understand how concerning it is to see that your folders and subfolders are still present but appear empty.
To narrow this down, could you please confirm whether the messages are also missing when you sign in directly to Outlook.com using a desktop browser, or whether this only occurs in the Outlook app?
Please also try searching for one known missing message by its sender or subject and set the search scope to All folders. If the message appears, please let us know which folder Outlook shows as its current location.
This will help determine whether the messages were moved or are simply not being displayed in the affected folders.
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