Microsoft on-premises server product that runs Office Online.
Hi @Kitnicholson,
Welcome to Microsoft Q&A, and thank you for reaching out to us.
Based on your description, aside from the Q&A assist suggestions, I’d like to share an additional tip.
If your sent emails were lost during long period, the most effective recovery option is for you or your admin to run a Content Search in Microsoft Purview. This tool can search across all mailboxes in your organization, including deleted or moved items, even those that were hard deleted.
Once the email is located, you or your admin can export the search results and then import them back into Outlook.
I hope this help.
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