Hi @Olivia Fery ,
Log in to webmail to see if there are these emails, if so, you can check the following settings in the client:
- Check if the Cached Exchange Mode "Mail to keep offline" setting is configured to a value other than All.
- The misconfiguration of Views settings is also the cause of the Outlook not showing old emails. To fix this issue, you can choose to reset its default view settings. Click View and View Settings to open the Advanced View Settings window. Click Reset Current View and click OK to save changes.
- Also, you may try to check if your emails have been deleted. See this article on how to restore deleted emails in Outlook.
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