# Quicktime Player Can't Open An .mp4 File



## Oriole (Oct 18, 2014)

I paid for and downloaded https://www.youtube.com/watch?v=iYZ2Ks8Jx8o, an .mp4 file, but was told that my Quicktime Player couldn't open it. I've never had this problem before, .mp4 being my usual download format, though I usually download them using DownloadHelper. But I play them back on Quicktime Player which has .mp4 at the top of its list of playable formats.

I complained to Metrodome / YouTube who promptly refunded me, but with a variety of explanations:

I would need to take up any download problems with the _"platform"_ but, subsequently:
_"YouTube paid content is for online streaming and cannot be downloaded"_ and that . . .
_"paid content uses slightly different technology unlike free videos",_ but that . . .
_"paid movies and TV shows can be saved for offline viewing on your Android, iOS or Chromebook device"_ provided there is a _"Play Movies & TV App on your device"_. Then, finally . . .
 _"Any issues with playback should be addressed to Google"_. - I take it that _"Google"_ here is the _"platform"_ referred to in the first item above . . . 
But, despite them saying it can't be done, the Metrodome site allowed me to and I did download the video, in .mp4 format.

I don't understand. I don't use any of the Android, etc, options. And I would rather have the thing on my computer than have to go online for it every time I wanted to play it.

I would be grateful to anyone who an put me straight about all this.


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## Doctor X (Oct 18, 2014)

Not having had your problem let me wildly speculate for paragraphs as an excuse to avoid real, actual work. . . . 

Get *VLC*: *Linkypoo*. That may solve all of your viewing problems and you can ignore the rest of this. And, frankly, it tends to play better than *QuickTime*. Safe and reliable. 

If it does not it may have to do with copyright protection, and I defer to others on that note.

That being blathered, I do not download _paid_ videos from Youtube. The few free ones I do will either be that format or flv. This is why I suspect a copyright block. However, I find the newest--now rather old*--QuickTime 10.2* does not play everything well. It is "bloatware" in my opinion and you cannot edit with it--"Oh but use *iMovie* and *Final Cut Ultra-Pro*" yeah . . . yeah . . . yeah . . . 

I saved and regularly used the ancient *QuickTime 7.6.6* with the installed MPEG 2 codec you had to buy back in the Stone Age! which pretty much plays anything. If you have that and THAT does not play the video, I would suggest trying *VLC*.

--J.D.


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## Oriole (Oct 31, 2014)

Please excuse this belated response. Trying to find a download of the desired documentary - The Gatekeepers - and free if possible, blinded me to the simple solution of buying the DVD . . .

I have downloaded your recommended VLC player though; gets good recommendations from other users.

Thanks.


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## Oriole (Nov 21, 2014)

Hello DeviMariah,

Thank you for your interest and advice which I have noted.


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## emma24xia (Jan 14, 2015)

How did you download youtube videos? I have tried several free tools, but the video quality is so bad.


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## Oriole (Jan 17, 2015)

emma24xia said:


> How did you download youtube videos? I have tried several free tools, but the video quality is so bad.



I use DownloadHelper, a free add-on for Firefox users.


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## emma24xia (Jan 22, 2015)

Is your MP4 protected like iTunes purchased m4v movies? I know MOV would be the best accepted video for QT. My suggestion would be transcoding MP4 to MOV and then add to Quick Time.


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## Oriole (Dec 2, 2016)

ilovelibertyfreedom said:


> Resources: How to Solve can't Play MP4 on QuickTime?



Many thanks!


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## Doctor X (Oct 18, 2018)

See my Linkypoo for VLC.

Is it the "best?" It seems to play pretty much everything.

--J.D.


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## iXod (Mar 7, 2019)

I stumbled on this very old (and updated) thread while searching for a solution for QT Player 7 spitting out this error:

"The movie could not be opened.
An invalid sample description was found in the movie."

The video I attempted to open is H.264 (x264) encoded with AAC audio in an mp4 container. 

Yes, there are players that will do this, but I don't want to play the videos, I like that the tools in QT7 (export, etc.) are all in one package. 

I guess I'm just looking for confirmation that QT Player 7 can't do anything with this video even though it has scads of codecs and components in its Library folder and there's nothing I can do to get QT 7 to play nice. 

Thanks,
iX


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## parmil434 (Mar 14, 2019)

The same issue I am facing and that is why I also contacted Apple technical service but they told me that there is no fault in the system. So, can anyone tell me a way to solve this issue?


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## DeltaMac (Mar 14, 2019)

parmil434 said:


> The same issue I am facing and that is why I also contacted Apple technical service but they told me that there is no fault in the system. So, can anyone tell me a way to solve this issue?


VLC is still a good solution - https://www.videolan.org/vlc/index.html
Are you saying that VLC does not work for you?


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