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We have Windows Vista and PowerPoint 2007. We have a presentation with embedded videos (.wmv & .mov). When we connect a Dell projector we can (of course) view all the slides on both the laptop and the projector, but not the embedded video.

When we press F8 the view switches between laptop only, laptop only (again), projector only and back to laptop only.

How can we get the video to play on both the laptop and the projector simultaneously?

The weird thing is that this used to work!

One other note - I've followed some internet instructions (example) but the Change settings button on the Troubleshoot tab (on Multiple Monitors) was disabled!

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I assume that the videos work when you are using the laptop screen. – ChrisF Sep 25 '10 at 16:44
@ChrisF - yes, they do. – Wikis Sep 25 '10 at 17:18
up vote 2 down vote accepted

When you say it used to work, was it the same laptop?

Has anything else changed on the laptop? New video playback software?

The only thing I can think of is that the external video output of the laptop isn't accelerated and the video playback requires hardware acceleration.

In much the same way as 3D graphics requires processor power on the actual graphics card (GPU), displaying video is quite processor intensive so you can improve performance by delegating it to the graphics card. It could be that the graphics card doesn't enable this acceleration on the external video output (the one you use for the projector). This could result in anything from a choppy video to a blank screen.

Now, if the setup used to work something must have changed, whether it's new video drivers (which have been known to make things worse) or a fault developing on the card etc.

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@ChrisF - thanks for the quick reply - yes same laptop, same projector. – Wikis Sep 25 '10 at 16:46
@ChrisF - "the external video output of the laptop isn't accelerated and the video playback requires hardware acceleration" - what do I need to do to solve it? In simple language please... =:-) – Wikis Sep 25 '10 at 17:11
@ChrisF - thanks again. No, nothing was changed to my knowledge except Windows Vista updates. I tried updating again today and there was no change. – Wikis Sep 25 '10 at 17:22
@Mark - it could be that the video card has developed a fault. – ChrisF Sep 25 '10 at 17:23
@ChrisF - what do I then need to do - does it require a new card? – Wikis Sep 25 '10 at 17:26

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