Some file types that are viewable on iOS may not display a preview when opened on a Mac. For these files, it is recommended that you download them to your computer and open them in their respective applications. This includes files such as .key (Keynote), .ai (which only shows the first page of the document), and .xd (wherein the preview might be unavailable), and others. Please ensure to download such files to your computer for a complete review by clicking on 'share' and then 'save'.