Sending, receiving, and organizing email in Outlook.com
Hi Justin W,
Since the same cutoff date appears in Outlook on the web, mobile, and desktop, this does not appear to be a device-specific sync issue. It suggests the mailbox content itself may be affected rather than a local Outlook setting.
One additional check you can try is verifying whether the account is displaying the correct mailbox:
- Sign in to Outlook on the web.
- Select your profile picture in the upper-right corner.
- Confirm you're signed in with the expected Microsoft account and not an alternate account or alias.
- If the account has multiple aliases, try sending a test message to each alias and verify where it arrives.
You can also check the mailbox storage view:
- Go to Settings > General > Storage.
- Review the folder sizes and message counts shown there.
- If older mail exists, unusually large folder sizes may help identify where messages are currently stored.
If the email history is still unavailable after these checks, I recommend contacting Outlook.com Support for a more detailed review of the mailbox, as they may be able to investigate account-specific mailbox data that is not visible through Outlook clients.
I understand how concerning it can be when a large portion of your email history is no longer accessible. Hopefully these checks help narrow down the cause, and I wish you the best in recovering your messages.
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