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Trying to play mp4 video, have VLC and VLC plug-in upto date, but it won't play- just hangs (Win XP)

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  • 14 zinale nkinga
  • 870 views
  • Igcine ukuphendulwa ngu emzfi

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Space for video screen opens, but controls don't work, it just sits there.

All Replies (20)

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What do you see if you right-click the player?

Firefox can play MP4 files natively with an HTML5 media player if the video element is used instead of the object or embed element.

You can try to set the media.directshow.enabled pref to false on the about:config page to disable the HTML5 media player.

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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The page opens with a VLC logo in the center. No clicking works. The controls at bottom don't work. The only thing that works is maximizing the page to full screen.

In about.confg, there are only three references to htlm5, two to flush and one to offline... none seems to refer to disabling the html5 player.

Thanks for the reply!!

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Further, trying toggling the "media directshow" to disabled made no discernible difference except the background of the video-ready page turned from black to white...

Thanks again!

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Since this question is not drawing any solutions, could somebody please indicate how to submit this problem to Firefox as a bug? Thanks!

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There's a nice article on how to write a bug report here: https://developer.mozilla.org/docs/Mozilla/QA/Bug_writing_guidelines

Are you getting a plugin notification on the address bar for VLC (looks like a piece of Lego)? If so, is VLC allowed to run on that site or does it need permission to run?

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First, I usually get a "Warning: Unresponsive plugin" message window to come up. If it does come up, after a few moments the message window disappears, and a full screen shows up with the VLC logo in the center, background is black. The start video button at the bottom of the screen appears, and it seems to click, but nothing happens...

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From your description, it sounds like VLC can start up, but it is having a problem reading media or otherwise interacting with Firefox.

In case one of your extensions is involved, could you test the page in Firefox's Safe Mode? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Troubleshoot Firefox issues using Safe Mode.

You can restart Firefox in Safe Mode using either:

  • "3-bar" menu button > "?" button > Restart with Add-ons Disabled
  • Help menu > Restart with Add-ons Disabled

Not all add-ons are disabled: Flash and other plugins still run

After Firefox shuts down, a small dialog should appear. Click "Start in Safe Mode" (not Reset).

Any difference?

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Other than the steps occur slower than before, no difference. The "Unresponsive plugin" comes up, click continue, eventually the black screen with the VLC logo comes up, but the buttons are unresponsive. So I guess no conflict with an extension?

Many thanks!

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Any idea what kind of media VLC is trying to play? I don't use VLC.

If it is MP4 video, have you considered having Firefox play it directly (using the DirectShow feature of Windows XP)? You might have disabled this at some point in order to facilitate downloading MPEG-encoded media.

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That's the strange thing... it must be a Firefox issue because if I try to play the mp4 video directly with VLC on the XP box, without bringing Firefox into the picture, VLC plays it just fine!

I need to make this work simply because the video is going onto a website and I need it to play directly, without special features that others may not have enabled (such as DirectShow you mention.)

Also strange: besides the XP box, I tried this on two Windows 7 computers, all using the same versions of VLC and Firefox, and with the proper VLC plugin... It doesn't play on the XP box, and also fails on one of the Win 7 boxes, but it plays just fine on the second Win 7 (a laptop.)

thanks!

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I can test in Windows 7 without VLC, if you like. I will need the link.

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Thanks much, but unfortunately I don't have authorization to distribute this particular video... it's been uploaded to a website. I could upload another, public video to do this test, but I figure finding out it works with another player won't answer the question Why doesn't VLC play the video in Firefox, since it works when playing the video outside of Firefox, and Firefox has the proper plugin?

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So this problem doesn't happen with other MP4 videos, only this particular one?

I don't know that any of the volunteers here are expert enough to guess the problem without hands on. You could post a description of the symptoms on the VLC forum and see whether they know the cause of the problem: https://forum.videolan.org/viewforum.php?f=21

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Your question is a very good one- is this a problem with this particular mp4 file? To answer your question, I uploaded another random mp4 file to the same web location and link, and exactly the same situation occurred: the VLC window opens, but nothing comes up and the buttons are not operational.

So the problem has nothing to do with this one particular video...

I should also have mentioned that when I open Chrome instead of Firefox in the same XP computer with VLC as the player, it plays perfectly.

So it's clearly a Firefox and/or a Firefox plugin problem. I am amazed that nobody else is observing the same problem... The VLC plugin currently installed in Firefox, btw, is 2.1.3.0.

I will also do as you suggest regarding the VLC forum.

Many thanks!

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VLC does play MP4 files, but it has strict limitations: VLC Media Player is only compatible with MPEG-4 ASP, DivX 4/5/6, XviD, 3ivX D4 and H.264 / MPEG-4 AVC. However, MP4 is a multimedia container format with many kinds of video and audio codecs. If your MP4 file contains a VLC unsupported audio or video codec, VLC won't play it.

Here is a step by step guide on how to successfully solve "VLC not playing MP4" issue with ease.

Hope it will help you more or less.

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Thanks for your response.

This is not a problem of VLC being able to play these mp4 files. When I open V LC stand-alone it plays these videos just fine. The problem only occurs when I try to play the same videos from a website page opened with Firefox. Further, Chrome does not have a problem reading the same video files from the same webpage. You'd think this points to a problem with the Firefox VLC plug-in, but nobody is pointing to this or how to fix it.

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Hi emzfi, from what you have described, everything is working normally up to the time Firefox declares that the VLC plugin is unresponsive, and then retracts the message and shows the player controls.

Then it sounds as though the video either fails to download or chokes the plugin.

You indicated that Safe Mode does not work better, so it the problem is not interference by an extension.

You indicated that if you download the file it plays fine in the stand-alone player.

You indicated that another MP4 on the same server causes the same problem.

Could it be a problem with how Firefox or the VLC plugin requests the file from that server? Two thoughts for testing:

(1) Can you successfully play MP4 videos in the VLC plugin on a different server?

(2) If you drag and drop the video from your hard drive onto a Firefox tab, will the plugin play it?

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Hello jscher2000,

Sorry for the delay in responding. As per your suggestions:

1) Searching for random mp4 files on the web, I tried a few and they all play just fine by simply clicking on the desired file icon.

2) Dragging the local video file from my hard disk into a Firefox tab produces the same result: The window opens, it's blank black, then the message "unresponsive plugin" comes up.

I should also note again that using Firefox on two Window 7 machines, (same Firefox version 33.0 in those as well as in he XP box) has no problem playing the videos with VLC. Thus the problem seems to be restricted to the XP version of Firefox.

Many tbanks!

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I think I have read that MP4s can use different codecs. It could be that something present on the Windows 7 systems is missing from Windows XP, but I'm not sure how best to diagnose that.

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If you can play the video in VLC then you can check the media and codec information in VLC to see what codec is used for video and audio.

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