Another computer problem has me stumped
 

Our daughter uploads videos of our granddaughter to an iCloud.
My wife can view/hear them on her computer when she clicks on them when accessing them via the web. She views them using Windows Media Player.
When she downloads the same video to her computer and clicks on the saved file, it only plays the audio portion, not the video.
I can download the same video to my computer and see/hear it just fine.
I tried sending the same file to her via email and she still can only hear but not see the video.
I don't get it.
How can she see/hear them perfectly when accessed via the web, but it won't play when she downloads it?
Any help would be appreciated.
She's running Win 7 Home Version 6.1.
I'm on Win 8.1 .

edit. The file downloads as an MP4 file type.

She is missing the required codec to play the file

https://support.microsoft.com/en-us/help/926373/you-receive-a-codec-error-message--or-audio-plays-but-video-does-not-p

You could try to find the correct codec, or try a different media player that would already have the required codec.

If that were the case, how does it play when accessed via the web?
Isn't the same media player playing it?

I would try QuickTime since the source files are from an apple device.

Try this info to see if it helps. I would say the video is playing on the cloud system and being streamed to your local PC. When you try to download it, the iCloud system goes into an anti piracy mode so no video content can be taken. There are a couple things to try: To check to see if the video has actually been transferred to your PC use the video player named VLC Media Player to try playing it. Also try software named "Handbrake" which is free and open the program to see what it says about video/codecs. A MP4 file can have just audio and not video.

https://www.coolmuster.com/ios-recovery/download-videos-from-icloud.html

Missing correct codec.

Grab VLC.

https://www.videolan.org/vlc/index.html

Thanks all.
I still don't understand why it would play via the net but not downloaded.
Anyway, I grabbed that VLC program and it seems to be working OK, at least on a short trial here at home. Wife is pleased now so that helps.
We'll just have to see how it plays out now.
Thanks again for the help.

Like watching a DVD or the same movie thru cable.
Thru cable, there is no running program on your tv decompressing audio and video. It just displays what is sent.
On your DVD player it is grabbing the digital stuff, decompressing and sending to tv. Think if the DVD had special stuff that you needed a code to play. Without the code, you have a disk, nothing else.

Codecs are extensions, libraries, that are available to apps that can use them.

But the app needs to be aware that they exist and know where to find them.

Web streaming, what a site displays in your browser is typically not the original source file.

When a user uploads a file it is often renecoded to a "friendlier" format and what you are seeing, what is being streamed is a lower resolution copy of the original.

This is done to make it more compatible and more often to make it band width friendly.

When you download the content locally you are getting the original unconverted source.

So the answer to "it works there but not here" is because what's here is not the same thing as what's there.

Not quite.

Your set top box is doing the processing.

It's functionally the same as the DVD player

+2 on VLC
it has all codecs built in the player
unlike most other players that use windows codec

Don't install Quicktime, not unless you want another Apple auto updating single use application