Can Windows play mp3 files when you double-click such a file in Windows Explorer?

Do you have this problem on all sites, or only on selected sites? You could try this test page, for example:

http://hpr.dogphilosophy.net/test/

The forum software detected your Firefox as version 24.0. Is that correct?

Version 24.0 is not secure; Mozilla discloses security flaws after each new release. Is something holding you back from upgrading to Firefox 27? Please let us know so we can suggest solutions or workarounds.

If you are running the "ESR" version of Firefox 24, Help > About Firefox should show your current version number to be 24.3.

Yes I can play mp3 files on my PC

Ran the test linked above, apart from mp3 and flac every format works

I'm running 24.3esr. I found it more stable than the next versions.

Are there any error messages about this in the Browser Console (Firefox/Tools > Web Developer)?

I'm going to need more to look that up. Can you give me a step by step instruction please. Also what do I look for in the console

You can open the Browser Console using Ctrl+Shift+j. It will display a stream of messages about lots of different things. Click Clear, then try the non-working activity again and look for any warning or error messages related to media.

See also:

• https://developer.mozilla.org/Tools/Browser_Console

(fixed broken link - c)

All right ran the console on the test page. Got the following message back:

-------------------------------------------------------------------------------------------------
[03:34:28.584] GET http://hpr.dogphilosophy.net/test/flac.flac [HTTP/1.1 206 Partial Content]
[03:34:28.751] HTTP "Content-Type" of "audio/flac" is not supported. Load of media resource http://hpr.dogphilosophy.net/test/flac.flac failed. @ http://hpr.dogphilosophy.net/test/
[03:34:31.487] GET http://hpr.dogphilosophy.net/test/mp3.mp3 [HTTP/1.1 206 Partial Content]
[03:34:31.928] HTTP "Content-Type" of "audio/mpeg" is not supported. Load of media resource http://hpr.dogphilosophy.net/test/mp3.mp3 failed. @ http://hpr.dogphilosophy.net/test/
[03:34:36.216] GET http://hpr.dogphilosophy.net/test/wav.wav [HTTP/1.1 206 Partial Content 2664ms]
[03:34:39.011] GET http://hpr.dogphilosophy.net/test/ogg.ogg [HTTP/1.1 206 Partial Content 549ms]
[03:34:39.553] GET http://hpr.dogphilosophy.net/test/ogg.ogg [HTTP/1.1 206 Partial Content 407ms]
[03:34:39.959] GET http://hpr.dogphilosophy.net/test/ogg.ogg [HTTP/1.1 206 Partial Content 2943ms]
[03:34:42.927] GET http://hpr.dogphilosophy.net/test/weba.weba [HTTP/1.1 206 Partial Content 2934ms]
[03:34:45.948] GET http://hpr.dogphilosophy.net/test/opus.opus [HTTP/1.1 206 Partial Content 568ms]
[03:34:46.482] GET http://hpr.dogphilosophy.net/test/opus.opus [HTTP/1.1 206 Partial Content 274ms]
[03:34:46.824] GET http://hpr.dogphilosophy.net/test/opus.opus [HTTP/1.1 206 Partial Content 4711ms]
-------------------------------------------------------------------------------------------------

Ran through all file types again so I could see the difference.

@cor-el your link give me a 404 error

I recently learned that my version of Windows (Win7 64b N) has no media player components maybe that is causing the issue. I'd prefer not to install Windows Media player only to resolve the problem. A work around would be better.

Media Foundation should have shipped with Windows; it is not optional, and I don't think additional downloads should be required. I searched for whether there is a way to disable it at the system level, and didn't see any (other than deleting its files, which seems unlikely). So most likely you have it and if you install most Windows updates, it should be up-to-date enough to handle MP3s.

Solved the problem, installed the Windows Media Feature Pack (http://support.microsoft.com/kb/968211) which gives you the Media Player, DVD Maker and Media Center. I've deactivated those three via the Control Panel and still got MP3 support. :D

Thank you for your help