You can select how you want to deal with duplicate items under “Options” here.

You can select how you want to deal with duplicate items under “Options” here.

Make sure you have your Outlook version installed through your Office 365 subscription. If you have a different version, you can download the installer at https://www. microsoft. com/en-us/download/details. aspx?id=45492. If you have a different version of Outlook the app icon may look like a yellow “O. " To view your Outlook version, click the Outlook tab on your Mac’s menu bar on the top-left, and select About Outlook. If you have the Office 365 version you’ll see “Office 365 Subscription” next to “License. “[1] X Research source