Play the video from its controls in PowerPoint’s editing view. If it plays there, select the video and open Playback > Start to see what triggers it in Slide Show. If it fails in the preview too, check the source file and how it was inserted.
01The clip plays in the editor but waits in Slide Show
Section linkSelect the video frame and open Playback > Start. With In Click Sequence, the clip starts at its turn in the slide’s sequence. With When Clicked On, click the video itself. Choose Automatically if you want it to start without a click. Check any preceding animations if it still waits, then replay the slide in Slide Show.
02The clip works on your computer but fails on another
Section linkThe slide may point to a video file stored separately from the presentation. On Windows, look for View Links under File > Info if PowerPoint shows it. If you shared only the deck, insert the original clip into a copy of the presentation using the regular Insert option so it is embedded. On Mac, the local video option is Movie from File. Test the copy on the computer that will run the show.
03The clip fails even in the editing preview
Section linkOpen the original file in a video player first. If it plays there, try exporting a copy as MP4 with H.264 video and AAC audio, the combination Microsoft recommends. Changing the filename to end in .mp4 leaves the encoding as it was. Insert the new file, set its start behavior, and check picture and sound in Slide Show.