Manatee

A video that will not play in PowerPoint on a Mac

· 6 min read

A video that will not play in PowerPoint on a Mac is nearly always one of three things: the file uses a format PowerPoint cannot decode, the slide holds a link to a file that has since moved, or the playback setting is waiting for a click you are not giving it. The dependable fix for the first is to convert the video to an MP4 with H.264 video and AAC audio, which is the combination Microsoft itself recommends, and insert it again. The other two take a minute each and need no conversion.

Work out which problem you have

The symptoms overlap, so run these checks before changing anything.

  1. Does the video play outside PowerPoint? Find the original file in Finder and open it in QuickTime Player. PowerPoint on a Mac leans on the media support built into macOS, so as a rule of thumb a file that QuickTime Player cannot open will not play on a slide either.
  2. Did it ever insert? If PowerPoint refused the file, or it appeared dimmed in the file chooser, the format is the problem.
  3. What does the slide show? A normal first frame that will not start suggests a playback setting. A black rectangle, sometimes with sound, suggests a codec problem. An empty placeholder suggests a broken link.
  4. Did it work on your Mac and fail on another computer? That points to a linked file that did not travel with the presentation, or to a codec the other computer lacks.

When the format is the problem

A file extension names the container, not what is inside it. Two files that both end in .mp4 or .mov can hold completely different kinds of video, and PowerPoint only cares about the contents. Container vs codec explains the distinction in full.

To see what a file holds, open it in QuickTime Player and choose Window, Show Movie Inspector. It lists the video and audio codecs along with the resolution. The usual troublemakers are:

  • MKV, AVI, WMV, FLV and WebM. macOS does not play these containers natively, so PowerPoint on a Mac will not take them.
  • HEVC (H.265), including video from a recent iPhone. It plays on a current Mac, but a Windows PC may need an extra codec component before PowerPoint there can show it.
  • Editing codecs such as ProRes in a MOV. They play on a Mac, make the presentation enormous, and frequently fail on Windows.
  • 10-bit or HDR footage, which can look washed out or refuse to play on older computers.

The fix is the same in every case: make a copy as an MP4 with H.264 video and AAC audio.

With QuickTime Player. If QuickTime Player opens the file, choose File, Export As, 1080p. If the export sheet offers a choice between greater compatibility and smaller file size, choose greater compatibility, which is H.264. The result is a MOV that PowerPoint on a Mac plays and that current versions of PowerPoint on Windows generally accept.

With Manatee. For files QuickTime Player will not open, or a folder of clips for one deck, Manatee does the conversion in one drop. Open it, choose Convert, drop the video in, and pick MP4. It accepts MKV, AVI, WMV, FLV, WebM, MOV and many other video types, and writes an H.264 MP4 with AAC audio next to the original, which is never modified. Everything runs on the Mac and nothing is uploaded, which matters when the clip is confidential company material. It is free for 24 hours with every feature, then $9 once. It is not a video editor, so if the clip needs trimming, do that in QuickTime Player (Edit, Trim) before you convert.

Then put the new file on the slide:

  1. Click the old video on the slide and press Delete.
  2. Choose Insert, Video, Movie from File (the wording varies slightly between versions) and pick the converted copy.
  3. Resize it and set its start option again.

Replacing the file in Finder is not enough. An embedded video is a copy stored inside the presentation, and the slide keeps the copy it was given.

When the link is broken

PowerPoint can embed a video or link to it. In the dialog where you choose the file, the Options button reveals a Link to file checkbox. With that checked, the presentation stores only the location of the video. Move the video, rename its folder, or email the .pptx on its own, and the slide has nothing to play.

Two ways to fix it:

  • Put the video back where the presentation expects it, with the same name.
  • Better, delete the video from the slide and insert it again with Link to file unchecked, so it travels inside the presentation.

Embedding makes the presentation larger, sometimes too large to email. Shrink the video before you insert it: Manatee’s Shrink mode takes a size in MB and finds the quality that fits. How to make a PowerPoint or Word file smaller covers the rest of the file.

One more cause sits here. The older .ppt format does not hold embedded video the way .pptx does, so a clip can end up as a link or as a still picture. Choose File, Save As, pick .pptx, and insert the video again.

When it is a playback setting

If the first frame shows and nothing happens during the slide show, select the video and open the Playback tab. The Start menu has three choices:

  • In Click Sequence: the video starts on the next click or key press, in order with any animations on the slide.
  • Automatically: it starts as soon as the slide appears.
  • When Clicked On: it starts only when you click the video itself. A presentation remote will move to the next slide instead.

Set it to Automatically if you present with a remote. While you are on that tab, check that the volume is not muted and that the clip has not been trimmed down to nothing.

Before you present on someone else’s computer

  • Save as .pptx with the video embedded, as an MP4 with H.264 and AAC.
  • Run the slide show from start to finish once after your last edit.
  • Carry the video file separately on the same drive. If everything else fails, you can play it outside the presentation.
  • If the deck is going into Keynote instead, see how to convert a video to MOV for Keynote.

Questions

Which video format is best for PowerPoint on a Mac? MP4 with H.264 video and AAC audio. It plays in PowerPoint on a Mac and on Windows, and in almost anything else you might fall back to.

Why does the video play on my Mac but not on a colleague’s Windows PC? Either it was linked and the video file was left behind, or it uses a codec the PC does not have, most often HEVC or ProRes. Embed an H.264 MP4 and both problems go away.

The video plays sound over a black rectangle. Is the file damaged? Usually not. That pattern means the audio could be decoded and the picture could not, which is a codec mismatch. Convert the file as described above.

What if the video will not play anywhere, even after converting? Then the file itself may be damaged. Manatee’s Repair mode reports Fixed, Partial or Not fixable, and writes any result as a new copy, so trying it does not put the original at risk.