To play Windows Media in Firefox, you need the Windows Media Player browser plugin installed. There are two different versions:

• The original, which is usually included with Windows up until XP.
• The new version, specifically developed for Windows XP and above, which is only available by download.

Mplayer is a popular Linux media player that can play back Windows Media files. In order to use Mplayer to play a Windows Media stream in Firefox, you must install two packages, named gnome-mplayer and gecko-mediaplayer. Your Linux distribution may have these packages readily available to install.

Microsoft discontinued the Macintosh version of Windows Media Player in 2006. The Flip4Mac replacement added Windows Media playback capabilities to QuickTime and was distributed for free until May 1, 2014, when Telestream began charging for Flip4Mac Player. For more information, see this Telestream article.

If you want a free player for many different media types, including Windows Media, you can try the VLC Media Player for Mac OS X. To play embedded audio and video content on web pages, you would need to download the VLC Web Browser plugin package (available from the Download VLC drop-down menu). For other alternatives, try the Mac App Store.

Checking if the plugin is installed

To see if you already have the plugin installed:

1. Click the menu button , click Add-ons and themes and select Plugins.
2. Scroll down the list, and look for the entry called:
   Microsoft® Windows Media Player Firefox Plugin
   np-mswmp.dll
   
   
   
   • If the entry is present, then the plugin is installed.
   • If the entry is missing, proceed to the Installing the plugin section.

Installing the plugin

1. Go to the plugin download page on Interoperability Bridges.
   • The Interoperability Bridges page also contains more detailed installation instructions.
2. Click "Download Now" and you will be prompted to save a file.
3. Save the file to your desktop.
4. Once it has downloaded, run it, and the plugin will install.
5. When the installation has finished, close Firefox:
   • Click the Firefox menu and select Exit.Click the Firefox menu at the top of the screen and select Quit Firefox.Click the Firefox menu and select Quit.
6. When Firefox has completely closed, start Firefox up again.
7. Type about:config in the address bar and press EnterReturn.
   A warning page may appear. Click Accept the Risk and Continue to go to the about:config page.
8. Search for plugins.load_appdir_plugins.
9. Double-click plugins.load_appdir_plugins to change its value to true.
10. Click the Firefox menu and select Exit.Click the Firefox menu at the top of the screen and select Quit Firefox.Click the Firefox menu and select Quit. When you restart Firefox the plugins will be enabled.