Thursday, January 31, 2008

Register MMS protocol in Firefox

Update: Surprisingly this post (originally posted in January 2005) still seems alive 3 years after my post. I should warn that I have not tried this method with Firefox versions later than 1.0 and have only tried it on Suse Linux Personal 9.1. If you need help please post a comment and I will try to help. I no longer use Suse and have since moved to Ubuntu (currently using Dapper LTS since I don't have time or need to update often) but will try to help as much as I can. Please see the comments on this post to see if someone has already tried to achieve what you want to.

Update Oct 20 2010: I received a comment ( on this post that links to a solution at I have not tried this solution so your mileage may vary.

MMS stands for Microsoft Media Services and as the Microsoft site says it is a proprietary streaming media protocol. This means that Internet Explorer (IE) has this protocol registered by default but Mozilla Firefox will need some tweaking before it lets you play mms:// streams.

I have tested this on Mozilla Firefox 1.0 (rpm version = MozillaFirefox-1.0-2.1) on Suse Linux Personal 9.1 and also Fedora Core 3. I believe this method will work on other versions of Mozilla Firefox and Linux OSs but have not tested them. Also the method suggested here is per user alone and not per install. I have included mplayer as the multimedia application that will play the mms:// stream. I assume that you have mplayer installed properly and able to play mms:// streams. You can try other media players but I have not tested others.

NOTE: Entering values/names/url's should be done without quote marks.

  1. In the URL bar of Firefox type "about:config".
  2. You need to create two new values as follows:
    1. Right click in the Firefox main window, click on "New" and select "String".
    2. In the text box that pops up type "" for the preference name. Click OK.
    3. For Value enter "/usr/local/bin/gmplayer". This is where my gmplayer is installed. If you have it in a different location, type that in for the value. To find where gmplayer is installed on your computer enter whereis gmplayer in a console. Enter the value that the "whereis" query outputs. Click OK.
    1. Right click in the Firefox main window, click on "New" and select "Boolean".
    2. In the text box that pops up type "network.protocol-handler.external.mms" for the preference name. Click OK.
    3. For value enter "true". Click OK.
At the end of this process you should have these two new values (type mms in the filter text box in the about:config window)

- Preference name:
Status: user set
Type: string
Value: /usr/local/bin/gmplayer

- Preference name: network.protocol-handler.external.mms
Status: user set
Type: boolean
Value: true

Now go to a site that provides mms:// streams and test. If this does not work, then I would suggest that you test to see if your default player can play the mms:// streams. Pass the URL of the mms:// stream to mplayer directly using the command line/GUI. If it plays then try a different profile in Mozilla Firefox and see if that works (you can create a new profile by using either the" firefox -P" or the firefox -ProfileManager" commands).


  1. This is excellent. Thanks for providing it. I got the link from the SuSE mailing list.

  2. Thank you for this excellent tip. Though I'll use VLC, mplayer seems to have some troubles with certain streams.

  3. Thanks. I tried it in Slackware 11 with xine and gxine. Works fine. Great!!!

  4. Did not work on my Mac. I had to install and use the MoreInternet preference pane to get VLC to work.

  5. This worked for me with firefox 3.5.2 but NO LONGER works for firefox 3.6 and I can't find anyone who knows why.
    I'm using /usr/bin/mplayer and when I give it an mms:// argument in a terminal it plays okay, so there is nothing amiss with mplayer handling mms protocol. (I also tried changing the protocol handler to use /usr/bin/gmplayer---note the "g"---but made no difference.)
    So firefox is just not handing the job over to mplayer properly.
    Would appreciate a solution .......! [am using puppy linux]

  6. Sorry Anonymous. I haven't tried this trick of mine in a long time, so not sure if something changed in Firefox 3.6.

    A previous commenter wrote that they "had to install and use the MoreInternet preference pane to get VLC to work". Would this be a possible solution to your problem?

  7. Mozilla made some changes and now you need three lines to do that instead of two, at least that's what worked for me (using 3.6.10). Here's a link to the thread I found it from: