Not sure which version you're currently running, see What version of Outlook do I have? Classic Outlook on Windows. If your accounts are supported in the new Outlook for Windows, you'll see a toggle in the upper right of classic Outlook to Try the new Outlook.. Selecting this toggle will download the new app and let you switch to the preview.

注意: 由于通知设置，某些用户在Windows 更新后的第一小时内看不到通知。 (若要检查此项，请选择“开始”gt;设置 > 系统 > 通知 >“打开”不会自动打扰，并查看是否选中 Windows 功能更新后的第一小时。。) 若要在看到通知之前更改动态照明设置，请按照上述步骤操作。