opening mp4's with VLC results in a malware warning

[seggy]

M4P Mini, Sequoia.2, freshly downloaded / installed VLC for AS.

I almost hit the default to delete, that would have been a problem.

I set VLC as default for the file type, and the moment i open an mp4 file it tels me it's got malware - then it proceeds to re-hijack the MP4 open back to QuickTime. When I set it back, same problem.

???

 

[Sciuriware]

M4P Mini, Sequoia.2, freshly downloaded / installed VLC for AS.

I almost hit the default to delete, that would have been a problem.

I set VLC as default for the file type, and the moment i open an mp4 file it tels me it's got malware - then it proceeds to re-hijack the MP4 open back to QuickTime. When I set it back, same problem.

???

I can play *.mp3 & *.mp4 on VLC without any problem. My situation is probably different so I tried to copy yours:

VLC media player 3.0.20 Vetinari (Apple Silicon)
MP4 video from Sony DSC-WX350 camera 62Mb.
Right clicked on file: Open With VLC.

Plays without a problem.
Can you check that scenario?
;JOOP!

 

[Sumleilmus]

I've been using VLC on mp4 files for 14 or more years. What do you mean by "VLC for AS?"

My mp4 files are all transcoded by Handbrake. What is or are the provenance(s) of your mp4 files? Are any of them downloaded?

When you write "it tels me it's got malware," what do you mean by "it?" An untrimmed screenshot that shows the error message would help, perhaps.

 

[seggy]

I've been using VLC on mp4 files for 14 or more years. What do you mean by "VLC for AS?"

My mp4 files are all transcoded by Handbrake. What is or are the provenance(s) of your mp4 files? Are any of them downloaded?

When you write "it tels me it's got malware," what do you mean by "it?" An untrimmed screenshot that shows the error message would help, perhaps.

Apple Silicon

The MP4 files are all sitting on a Synology NAS. The particular file in question was a rendered file from an edit done in Windows.

Directly opening an MP4 file with VLC = fine

Setting VLC as default opener for MP4 files then double clicking on file = "Apple could not verify [filename] is free of malware that may harm your Mac or compromise your privacy" 😕

 

[seggy]

I can play *.mp3 & *.mp4 on VLC without any problem. My situation is probably different so I tried to copy yours:

VLC media player 3.0.20 Vetinari (Apple Silicon)
MP4 video from Sony DSC-WX350 camera 62Mb.
Right clicked on file: Open With VLC.

Plays without a problem.
Can you check that scenario?
;JOOP!

What I said above. I can open the files from VLC or by "open with" just fine.

When I set VLC to default MP4 app is when I have the problem.

 

[chevman]

Check recommendations here - https://discussions.apple.com/thread/255842085?sortBy=rank

 

[seggy]

Check recommendations here - https://discussions.apple.com/thread/255842085?sortBy=rank

Thank you. Worked. In case anyone else wades into this thread, the solution is to open the Finder Info pane and set the default app from there instead.

This is unbelievably dumb.

It just goes to highlight yet another element of why I collapse into hysterical laughter every time they say The World's Most Advanced OS. What is more is these days is The World's Most Bugridden OS.

 

[bogdanw]

There are two solutions for this problem (first one already mentioned above):

1. Set the default app to open mp4 files from Finder. “Permanently change the app used to open all files of a particular type” https://support.apple.com/guide/mac-help/choose-an-app-to-open-a-file-on-mac-mh35597/mac

2. Remove the quarantine attribute for the mp4 files from Terminal. Example to remove quarantine for all mp4 files in the Movies folder:

xattr -d com.apple.quarantine ~/Movies/*.mp4

 

[seggy]

There are two solutions for this problem (first one already mentioned above):

1. Set the default app to open mp4 files from Finder. “Permanently change the app used to open all files of a particular type” https://support.apple.com/guide/mac-help/choose-an-app-to-open-a-file-on-mac-mh35597/mac

2. Remove the quarantine attribute for the mp4 files from Terminal. Example to remove quarantine for all mp4 files in the Movies folder:

xattr -d com.apple.quarantine ~/Movies/*.mp4

The bigger question is why only some of the open with solutions work.
And why it sometimes places entire devices under quarantine.

 

[Sciuriware]

The bigger question is why only some of the open with solutions work.
And why it sometimes places entire devices under quarantine.

If the problem should concern certain devices, may be, the problem has nothing to do with VLC.
;JOOP!

 

[seggy]

If the problem should concern certain devices, may be, the problem has nothing to do with VLC.
;JOOP!

it clearly doesn't, it looks to be a particularly sequoia problem since I didn't have anything like this in monterey

 

[bogdanw]

And why it sometimes places entire devices under quarantine.

Because

The MP4 files are all sitting on a Synology NAS.

are probably regarded as being downloaded, coming from an untrusted source.

 

[Sciuriware]

it clearly doesn't, it looks to be a particularly sequoia problem since I didn't have anything like this in monterey

Moreover, I have seen all kinds of problems with external drives since Ventura.
May be MacOS is too careful with external disks.
Then again, in all those releases I never had a problem making CCC backups on external Seagate's ...

Could this problem be restricted to networked drives?
;JOOP!