If that slide contains animations, you’ll need to take this into account because the thumbnail will be generated from what you see in the normal view, not the slide show view.

Preview thumbnails are created by PowerPoint taking a static capture of your first non-hidden slide.

This makes it easy to see what each file contains! So how do you activate these thumbnails? Here’s an example of three presentations with the preview thumbnail set in each PowerPoint file: Providing a visual cue of the file’s content can also help improve accessibility for your users. You might be happy to create and distribute your beloved PowerPoint content using these default icons but when you have a lot of them all in the same place, it’s nice to see a preview of what’s inside the separate files. How to create custom PowerPoint preview thumbnail icons If you add macros to any of these files the formats change to ones ending in ‘m’ and the icons change, illustrating the presence of macros with an exclamation mark (Office 365 / PowerPoint 20): These icons correspond to the three ‘standard’ formats: presentation, template and slide show. When you view these three formats in Windows File Explorer, the icon you see reflects that format or file extension: And if you save your presentation as a self-starting slide show then ppsx is used. When you create a template the extension used is potx. You may or may not know that when you save a presentation it’s saved as a pptx file. You’re about to learn everything you ever needed to know about how these work, how to generate them, and how to get rid of them. Have you ever noticed the PowerPoint icons that show up on your desktop or inside Windows File Explorer? Sometimes the default application icon is shown and sometimes you see a PowerPoint preview thumbnail of a slide from your presentation.

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