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Need to open video files in external viewer

  • 7 replies
  • 11 have this problem
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  • Last reply by philipp

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I work in an audio/video studio. We have an internal web based project management system, where we keep mp4's of all approved versions of video projects. Before today, I could click on any video file, and it would automatically open in an external viewer (quicktime) which is necessary because sometimes I have to open multiple videos simultaneously and compare them.

Today however, every time I click on one, it opens in a Firefox window. I have gone into Tools>Options>Applications and manually changed MP4 to open in Quicktime. But the files continue to open in Firefox window, which makes it impossible to open 2 files for comparison.

Please help me get this back to the way I need it to work!

I work in an audio/video studio. We have an internal web based project management system, where we keep mp4's of all approved versions of video projects. Before today, I could click on any video file, and it would automatically open in an external viewer (quicktime) which is necessary because sometimes I have to open multiple videos simultaneously and compare them. Today however, every time I click on one, it opens in a Firefox window. I have gone into Tools>Options>Applications and manually changed MP4 to open in Quicktime. But the files continue to open in Firefox window, which makes it impossible to open 2 files for comparison. Please help me get this back to the way I need it to work!

Chosen solution

enter about:config into the firefox location bar (confirm the info message in case it shows up) & search for the preference named media.windows-media-foundation.enabled. double-click it and change its value to false - this will also disable native html5 playback support for mpeg formats that are embedded into websites though.

another way to download the files without tweaking the preference mentioned above would be to right-click the files and choose to download the like that...

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and to add more to the mystery- some of the MP4 files won't play in the Firefox window- it says "video can't be played because the file is corrupt". However the file is not corrupt- I can right click on it, save it to my desktop, and then play it with Quicktime with no problems. Again, this is an issue that just started today.

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Just discovered that mp3's are doing the same thing- I have Tools>Options>Applications set up with mp3's to open in external default viewer, but Firefox (as of today) is opening them in a Firefox window. What happened to my firefox????

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Chosen Solution

enter about:config into the firefox location bar (confirm the info message in case it shows up) & search for the preference named media.windows-media-foundation.enabled. double-click it and change its value to false - this will also disable native html5 playback support for mpeg formats that are embedded into websites though.

another way to download the files without tweaking the preference mentioned above would be to right-click the files and choose to download the like that...

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Thank you thank you thank you!!! Now I can work normally again!

Any idea how/why that changed today?

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the option to use the windows codecs to natively play mpeg content was turned on in firefox 21 (so you've likely updated today)...

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AH! Ok... It's been driving me nuts for hours trying to "fix" this thing. I really appreciate your help.

Since I only use this computer for work, I need it to "work" ;-)

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you're very welcome - so, back to work... ;-)