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Error appears when I try to play a m4v format video

Hi Everyone,


I have an issue - I tried to play an m4v format video but this appears after I tried to open the video with Quicktime Player as my recommended app (but it was working fine earlier).


I'm not sure if I did anything but I'll describe what I did previously:

- A couple of days ago, when I selected any of my m4v videos, quicktime player would automatically open up and I'll be able to play my videos.

- However, I have another video that uses an "flv" format video and that can't be played using quicktime (I installed VLC player).

- After the installation of the VLC player, I'm unable to play my m4v videos.


Any advice?


Please help!!!


User uploaded file


Regards,

Brandon

MacBook Pro (Retina, 13-inch,Early 2015), OS X Yosemite (10.10.5)

Posted on Sep 27, 2015 4:06 PM

Reply
Question marked as Best reply

Posted on Oct 4, 2015 4:34 AM

I have an issue - I tried to play an m4v format video but this appears after I tried to open the video with Quicktime Player as my recommended app (but it was working fine earlier).


I'm not sure if I did anything but I'll describe what I did previously:

- A couple of days ago, when I selected any of my m4v videos, quicktime player would automatically open up and I'll be able to play my videos.

- However, I have another video that uses an "flv" format video and that can't be played using quicktime (I installed VLC player).

- After the installation of the VLC player, I'm unable to play my m4v videos.


Any advice?

As the modal message indicates, whatever you are doing is causing your system to try and open an app downloaded from an "unidentified" developer while your current "Security & Privacy > General" System Preferences setting only allows you to open apps downloaded from the Mac App Store and identified developers. I suspect your recent activities may have inadvertently changed your "open with" object class setting for your M4V files.


You can either check the "open with" object class association in the Finder "Get Info" or Context Menu window and change it if necessary or change the "System Preferences > General > Allow apps downloaded from:" option from "Mac App Store and identified developers" to "Anywhere" to prevent the modal message from being displayed and thus allow the offending app to open normally and either play the M4V file or provide a secondary error message indicating the offending app cannot play the M4V file. In either case, you can then associate the M4V object class back to the iTunes default app setting or the QT player of your choice.

User uploaded file

3 replies
Question marked as Best reply

Oct 4, 2015 4:34 AM in response to 1Brandon_E

I have an issue - I tried to play an m4v format video but this appears after I tried to open the video with Quicktime Player as my recommended app (but it was working fine earlier).


I'm not sure if I did anything but I'll describe what I did previously:

- A couple of days ago, when I selected any of my m4v videos, quicktime player would automatically open up and I'll be able to play my videos.

- However, I have another video that uses an "flv" format video and that can't be played using quicktime (I installed VLC player).

- After the installation of the VLC player, I'm unable to play my m4v videos.


Any advice?

As the modal message indicates, whatever you are doing is causing your system to try and open an app downloaded from an "unidentified" developer while your current "Security & Privacy > General" System Preferences setting only allows you to open apps downloaded from the Mac App Store and identified developers. I suspect your recent activities may have inadvertently changed your "open with" object class setting for your M4V files.


You can either check the "open with" object class association in the Finder "Get Info" or Context Menu window and change it if necessary or change the "System Preferences > General > Allow apps downloaded from:" option from "Mac App Store and identified developers" to "Anywhere" to prevent the modal message from being displayed and thus allow the offending app to open normally and either play the M4V file or provide a secondary error message indicating the offending app cannot play the M4V file. In either case, you can then associate the M4V object class back to the iTunes default app setting or the QT player of your choice.

User uploaded file

Oct 4, 2015 4:36 AM in response to Jon Walker

Hi Jon,


Alright, your suggestion did work. However, I'm still curious, the M4V files were downloaded from my university system and it's odd because I'm able to open it via VLC player with ease but when I try to open it with Quicktime Player (an Apple software), it's blocked (screenshot displayed above in the original message).


Is there an alternative way to fix this issue without turning off the privacy and security settings?

Oct 4, 2015 6:43 AM in response to 1Brandon_E

Is there an alternative way to fix this issue without turning off the privacy and security settings?

Hard to say without actually observing your system in operation. I can think of a half dozen possibilities—each dependent on a different issue ranging from the use of a self-playing media app masquerading as a video file to the previously mentioned possibility of a change to the opening player app setting to some sort of a system conflict/corruption or even the result of a security update by Apple.


Probably the simplest thing to check would be the "Open with" setting for the problem files. The default "Open with" player app for M4V files is the iTunes app as seen below:

User uploaded file


This setting can be different for each M4V file or can be applied to an entire class of file extensions. What is the setting for your problem M4V files and does your issue extend to all M4V files or just to the files downloaded from the university?

User uploaded file

Error appears when I try to play a m4v format video

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