Go to the App Store on your Mac, and search for OneDrive.To download OneDrive app from the App Store: If you have an older version, you should remove it and replace it with the latest version. An older version uses an icon of two supperimposed clouds with a darker shade of blue. The latest version uses an icon of a single cloud with three shades of blue. To verify this, search for OneDrive in Finder. If the latest version of Office 365 is already installed on your Mac, the OneDrive app should be installed on it as well.