Step-By-Step Guide: Embedded Windows Media in Firefox

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Step-By-Step Guide: Embedded Windows Media in Firefox

Post by Vectorspace »

Full Step-By-Step Guide: Embedded Windows Media in Firefox

WARNING!! Before you install the ActiveX plugin, if you use the Adblock Extension, you must make sure that the setting for OBJ-TABS is disabled. Otherwise, your system will run almost any ActiveX control. See <a href="#Notes">Note 4</a>.

  • Warp to <a href="#Background">Background</a>
  • Warp to <a href="#wmp">Windows Media Player Plugin</a>
    • <a href="#WMPSecur">Security Alert</a>
    • <a href="#CheckWMPn">Checking Windows Media Player plugin installation (XP/Vista)</a>
    • <a href="#CheckWMP">Checking Windows Media Player plugin installation (other)</a>
    • <a href="#RestoreWMP">Restoring the Windows Media Player plugin</a>
    • <a href="#ConfigWMP">Configuring/Troubleshooting the Windows Media Player plugin</a>
  • Warp to <a href="#FF_1">ActiveX Plugin</a>
    • <a href="#InstallAX">Installing the ActiveX plugin</a>
    • <a href="#CheckAX">Checking ActiveX Plugin Installation</a>
    • <a href="#Uninstall">Uninstalling ActiveX</a>
  • Warp to <a href="#Notes">Notes</a>
  • Warp to <a href="#Trouble">Troubleshooting</a>
Most of the ActiveX plugin information in this guide has now been mirrored in the Knowledge Base:

For other embedded/streaming media guides and information, visit the Complete Embedded & Streaming Quicktime/Real/Windows Media Player Guide for Windows Users.


<a name="Background"></a>Background

It is common to find websites that use Windows Media Player to embed audio and video into a web page. The Windows Media Player plugin, while not included with Windows Media Player, should be included with Windows itself - however this is not always the case. In addition, many websites use ActiveX only to embed media - making such websites IE-only. This guide discusses how to solve both problems.

If you came here wondering how to make Firefox use the Windows Media Player plugin play a specific file type instead of Quicktime, then you should know that the WMP plugin is hard-coded to only play the proprietary Microsoft formats (.asf, .asx, .wm, .wma, .wax, .wmv, and .wvx), and Windows Media Player provides no provision for changing this. For the most common formats found on the web (like mp3, midi, mpg, wav, etc.) you will need to install and configure Quicktime or Quicktime Alternative. The Quicktime guide contains instructions for this:


<a name="wmp"></a>Windows Media Player Plugin

Windows Media Player provides a plugin to allow browsers other than IE to display embedded Windows Media. It is this plugin that Firefox uses. Sometimes though, the plugin is missing or refuses to work properly. This section of the guide gives instructions on checking the plugin, restoring it if missing, and on configuring it if it doesn't work properly.

<a name="WMPSecur"></a>Security Alert
Microsoft issued a security bulletin on Feb 14 2006 regarding a vulnerability in the Windows Media Player plugin on Windows 2000 and Windows XP systems, that could result in remote code execution when using non-Microsoft web browsers. Affected users should install the "Security Update for Windows Media Player Plug-in (KB911564)" available from Windows Update. This will update the WMP plugin file "npdsplay.dll" to version ... 6-006.mspx

<a name="CheckWMP"></a>Checking Windows Media Player plugin installation
  • For this to work, you need to you have Windows Media Player 9, 10 or 11 installed. They can be installed through Windows Update.
  • You can test the Windows Media Player plugin here:If those test players work, then the Windows Media Player is installed.
  • If they do not work, you need to check that Firefox can detect the Windows Media Player plugin:
  • Windows XP/Vista Users
      A new Windows Media Player plugin has been released for these two platforms on Port 25, Microsoft's open source labs website. It is specifically for Firefox (it also works in Seamonkey). It is a significant improvement over the original plugin - it adds support for scripting, modern look skins, visualisations, and most (if not all) of the attributes that the ActiveX control in IE supports. It only works in Windows XP and Vista.
    • Type about:plugins into the address bar. This will display Firefox's plugin information. If the plugin is installed, you will see an entry entitled: "Microsoft® Windows Media Player Firefox Plugin"
  • Other versions of Windows
    • Type about:plugins into the address bar. This will display Firefox's plugin information. If the following entries are present, then WMP is installed correctly:
    • The "Microsoft® DRM" entry with the filename npwmsdrm.dll might be called "Microsoft Corp. DRM Netscape Plugin" instead.
    • If any of these entries are missing, the Windows Media Player plugin is not properly installed.
<a name="RestoreWMPn"></a>Restoring the Windows Media Player plugin (XP/Vista)
If any of the entries are missing, install the new Windows Media Player plugin from
  • The plugin will be automatically installed into Firefox's plugins folder. The plugin installer detects installed versions of Firefox from the Windows registry. Therefore only release versions that were installed using the installer will receive the plugin. Other Gecko browsers such as Seamonkey, and zip or development builds of Firefox will not.
  • If you have a release version of Firefox installed, the plugin will have been installed there. You can then copy the plugin - np-mswmp.dll - from the plugins folder of the release version to the plugins folder of any other versions you may have.
  • If you do not have a release version, the plugin file will be located at "C:\PFiles\Plugins\np-mswmp.dll". Copy it to the plugins folder of any other versions you may have.
<a name="RestoreWMP"></a>Restoring the Windows Media Player plugin (other)
  1. If any of these entries are not present, look for the files in the Windows Media Player directory (usually C:\Program Files\Windows Media Player), and if you find them copy then to the Firefox plugins directory (usually C:\Program Files\Mozilla Firefox\plugins). Then repeat the previous step and check the files are all there.
  2. <a name="dlldump"></a>If some of the files are still missing, you can download the individual files from them to the Windows Media Player directory (usually C:\Program Files\Windows Media Player) and then restart Firefox.
  3. If the plug-in files still do not appear, try copying them to the Firefox plugins directory (usually C:\Program Files\Mozilla Firefox\plugins).
  4. Special versions of Windows XP:
    • If you use Windows XP Home N or Windows XP Pro N, see Issue 7 in the following section (<a href="#ConfigWMP">Configuring/Troubleshooting the Windows Media Player plugin</a>).
    • If you use Windows XP Media Centre Edition, see Issue 12 in the following section (<a href="#ConfigWMP">Configuring/Troubleshooting the Windows Media Player plugin</a>).
If the plugin files are present but not functioning:
  • Install this update from Microsoft: ... lugin.aspx
    It installs the plug-ins plus some other files.
  • Download the thee plug-in files from and place them in Firefox's plug-ins folder (as mentioned above) - this is necessary because the plug-in installer from Microsoft contains older versions of the files, which have un-patched security holes.
If the plug-ins still are not functioning, consult the following section: "Configuring/Troubleshooting the Windows Media Player plugin"

<a name="ConfigWMP"></a>Configuring/Troubleshooting the Windows Media Player plugin

Known issues with the WMP plugin and (where applicable) the solution. These only apply to the old plugin.
  1. If, when playing a video, the video image is either invisible or disappears when you click a control, you need to adjust the plugin settings:
    • When the player is active, right-click on it and select 'Options...'
    • At the bottom of the window should be a 'Video Acceleration' option. Change it from full to half (or to zero, if needed) by moving the slider.
  2. Firefox crashes on exit if the WMP plugin has been used (Windows 2000)
    • Double-click on the 'My Computer' icon on the desktop, then double-click on 'Control Panel'.
    • Double-click on the Java icon to bring up the Java control panel.
    • Click on the 'Update' tab, and then the 'Update Now' button.
      This problem can sometimes be caused by not having the latest version of the Java plugin.
  3. <a name="Patch"></a>If the player controls look like they are from an older version of Windows Media Player:
    • Right-click this link and save it to your desktop:
    • When it has downloaded, double-click it. A pop-up will ask if you want to add the information in it to the registry - click Yes.
      If the registry patch doesn't help, it has been reported that reinstalling Windows Media Player 10 will work.
    • The WMP plugin is the same whether you use WMP 6.4, 7, 9, or 10 - this registry patch basically allows Firefox to apply the modern WMP look onto the plugin.
  4. "Can not create DirectShow Player" error: I have never experienced this error, so I an not clear on why it occurs. It was recently reported that it could be a symptom of this problem: So try the solutions there first.
    Failing that, try reinstalling WMP and installing the latest version of DirectX. Windows XP users with WMP 9 can try upgrading to WMP 10, and WMP 10 users can also try rolling back to WMP 9. It has been reported that booting Windows in Safe Mode, deleting WMP, then reinstalling WMP will solve it. I have not tested this method (having never had the error), so I do not know if it will work and I do not know what possible side-effects manually deleting WMP in this manner could cause. In any case, try the other possible solutions first.
  5. The players in the test links here have the status bar - it tells you what the player is doing. This is not always the case. Sometimes when you hit play on a player without a status bar, it seems like nothing happens - in fact, the player is probably just downloading enough of the file to start playing it (buffering) and if you give it a moment, it will start.
  6. Illegal operation in Windows Media Player plugin error. If you find you are getting the following when you try to watch embedded Windows media:

    Code: Select all

    Illegal Operation in Plugin
    Windows Media Player Plug-in Dynamic Link Library
    The plugin performed an illegal operation. You are strongly advised to restart Navigator.
    • This can be caused by having Javascript disabled.
    • Click Tools > Options > Web Features and make sure that Javascript is enabled.
    • Make sure that any extensions you might have that can block Javascript are not blocking the site in question or are disabled. These include NoScript and Adblock Plus.
  7. For users of Windows XP Home N or Windows XP Professional N:
    Because of a recent decision by the European Commission, Microsoft have been required to offer these new European versions of Windows XP Home/Pro in addition to the standard verisons, with Windows Media Player and all built-in media playback abilities removed - including the Windows Media Player plugin. The N stands for 'Not with Windows Media Player'.
    Because of the scope of the changes, you cannot simply install Windows Media Player to get full functionality back. Microsoft have released an update to convert Windows XP N to regular Windows XP (by restoring all the missing files). Users of Windows XP Home/Pro N will need to install this update to run the Windows Media Player plugin: ... layLang=en
    Warning: This cannot be undone. After installing this update, the only way to revert back to Windows XP N will be to re-install Windows.
    This update is also available on Windows Update.
  8. Player appears, player status bar says 'Ready', no error messages, but nothing happens when you click Play.
    For the Windows Media Player plugin to work, Internet Explorer must have access to the internet:
    • Make sure Internet Explorer is not set to Work Offline mode: To check if IE is in 'Work Offline' mode, open IE and open the File menu. There would be a tick by the 'Work Offline' option. Click it to take IE off Work Offline mode.
    • Make sure that Internet Explorer's proxy settings are correct.
    • Make sure that Internet Explorer and Windows Media Player are not blocked by your Firewall.
    This can also be caused by DSL/cable providers using Network Address Translation (NAT) not forwarding UDP packets properly. The solution is to disable UDP in Windows Media Player:
    • In WMP, click Tools > Options
    • Select 'Network'
    • Deselect 'UDP'
    It has also been reported that reinstalling/upgrading/downgrading Windows Media Player can solve this.
  9. Firefox crashes while typing to play embedded WMV files.
    This can be caused by having the VLC Media Player installed, which includes its own browser plugin. This plugin conflicts with the WMP plugin, so you need to remove the VLC plugin for embedded WMV files to play properly.
  10. Player does not appear, but audio (sometimes)still plays - all plugin files are listed in about:plugins:
    • It has recently been reported that under Firefox 1.5, Adblock's OBJ-TABS setting will block the WMP plugin. If you find this happens to you, disable the obj-tabs setting. If that doesn't work, try redownloading the plugin files from as descriped in the <a href="#dlldump">previous section</a>, and placing them in Firefox's plugins folder.
    • The VLC Media Player plugin has also been known to do this - remove the VLC plugin.
  11. Firefox - has a bug that interferes with the WMP plugin. Upgtade to
  12. Windows XP Media Centre Edition
    Windows XP Media Centre Edition does not come with the Windows Media Player plug-ins. In addition, often it appears incapable of supporting them so just restoring the dll files may not work, and the installer for the plug-ins does not recognise XP Media Centre Edition. It has been reported that the update for Windows XP N (XP with no media playback ability, see issue 7) that re-adds the missing media playback files will allow XP Media Centre Edition to support the WMP plug-ins.
    Warning:this update cannot be uninstalled. The only way to undo it is to re-install Windows, so attempt at your own risk. The update is here.


<a name="FF_1"></a>ActiveX Plugin (Firefox 1.0-1.0.8, 1.5-

Some Embedded/Streaming Media (such as those on use an ActiveX Control to embed Windows Media into a web page. ActiveX is what Internet Explorer uses instead of the plugin system adopted by Netscape. Where plugins are essentially sub-programs run within the browser (and so subject to whatever limitations the browser imposes on it), ActiveX controls are Windows programs, and so do not have limits imposed on them and what they are allowed to do. This gives them a lot of poential power over your system, especially coupled with the fact that IE can download and install them automatically and silently for you. The intention was to allow for more complex web page content, but the system can be and has been exploited to install viruses, adware, spyware, and the like. The power of ActiveX can be a big security risk, and is one of the more serious security vulnerabilities in IE. Partly for this reason, Firefox does not come with ActiveX support installed.
There are ActiveX plugins for Firefox avaliable, and this section of the guide gives instructions for installing and testing it. The security issue is bypassed because the plugins for Firefox come pre-configured to only run the Windows Media Player controls. It will simply refuse to download or run any other control, good or bad. This will allow you to view many of the websites that only use ActiveX to embed media.

An alternative to the ActiveX plugin is the Greasemonkey script IE Media Mimic: ... key/#mimic
Among other things, it can provide partial support for Windows media embedded with ActiveX, by converting the ActiveX object to a regular WMP object. At the time of writing, the author of IE Media Mimic does not consider it user-friendly enough for the average Firefox user, so read the info on its homepage thoroughly before you consider using it.

<a name="InstallAX"></a>Before You begin:
IMPORTANT. If you use the Adblock Extension, you must make sure that the setting for OBJ-TABS is disabled. Otherwise, your system will run almost any ActiveX control. See <a href="#Notes">Note 4</a>.

Before installing the ActiveX plugin, read the following:
  • This guide only applies to the official milestone releases of Firefox 1.0 to 1.0.8 and Firefox 1.5 to under Windows.
  • There is no ActiveX plugin for Firefox 1.0.5, but the plugin for Firefox 1.0.4 seems to work for it.
  • There is no ActiveX plugin for Firefox 1.0.8, but the plugin for Firefox 1.0.7 seems to work for it.
  • There is no ActiveX plugin for Firefox to, but the plugin for Firefox 1.5 seems to work for them.
  • The ActiveX plugin is not compatable with Moox builds. Compatability with other 3rd party builds is unknown.
  • For pre-1.0 versions of Firefox (also under Windows), see this earlier version of this guide:
  • The ActiveX plugin for Firefox 1.5 is marked as a test version - so there may be unknown problems with it.
  • Most methods of updating Firefox to a new version do not remove the ActiveX plugin, and there is no guarantee that the plugin version you have will work with the new version of Firefox. It is strongly recommended that you <a href="#Uninstall">uninstall</a> the ActiveX plugin before you update Firefox. Having the wrong version of the ActiveX plugin installed can cause other plugins (especially Flash) to malfunction.
Installing the ActiveX Plugin
<a name="CheckAX"></a><a name="TestAX"></a>Checking ActiveX Plugin Installation
  • You can test the ActiveX installation on this website: <a href="" target="_blank">ActiveX Test - Windows Media Player</a>
    If you can play both the audio and video players, then the ActiveX and Windows Media Player plugins are installed correctly.
  • If they do not display properly, type about:plugins into the address bar. If the following entry is present, then the ActiveX plugin is installed correctly:
  • If this entry is not present, then reinstall the ActiveX plugin.
<a name="stillno"></a>Embedded Media that still won't work
If the test link in the previous step worked, then the ActiveX plugin is working. So:
<a name="Uninstall"></a>Uninstalling ActiveX

Should you want to uninstall the ActiveX plugin, the process is simple - only four files need to be manually deleted from the Firefox program folder.
  • Close all instances of Firefox
  • Go to the Firefox program folder (the location you installed Firefox to). The default location in Windows is 'C:\Program Files\Mozilla Firefox\'
  • Go into the plugins folder and delete the file 'npmozax.dll'
  • Go back to the Firefox program folder, and then go into the components folder, and delete the files 'nsIMozAxPlugin.xpt' & 'nsAxSecurityPolicy.js'.
  • Go back to the Firefox program folder, and then go into the defaults\pref folder, and delete the file 'activex.js'.


<a name="Notes"></a>Notes

Note 1. With certain versions of ActiveX installed, sometimes the Flash plugin will not load unless it was previously loaded.
A work-around is to refresh your plugins (type about:plugins in your address bar) when starting FireFox, under those circumstances everything loads normally.

Note 2. AnonEmoose and I have tested these methods of installing ActiveX with many sites that use ActiveX to stream video (including video, Listen Live, video and others) with no problems. However, this does not guarantee that this will allow Firefox to view all embedded/streaming video - for example, some also use IE-only javascript in the embedded players.

Note 3. AnonEmoose has tested Yahoo/Launch Radio, and believes it does NOT work with Firefox

Note 4. For some reason, the OBJ-TABS setting in the Adblock Extension interferes with the ActiveX plugin. The activex.js file that is installed with the plugin determines which controls the plugin may and may not run. If the OBJ-TABS setting is enabled, then the ActiveX plugin will ignore activex.js and run any control.

Note 5. IE has a function whereby if you are downloading a video file (such as through a link), it can have WMP play the file as it is downloading. There are methods of duplicating this behaviour in Firefox here: ... 216#stream

Note 6. If you ever have trouble finding any files on your computer, make sure you have enabled the viewing of hidden files and folders in Windows folder options.

Note 7. If you ever have trouble playing media at a site that is reported to work in Firefox when using this method, try clearing all cookies set by that site, then re-trying. In addition, make syre that cookies for the site in question are not blocked (the Adblocker extension could also do this).

<a name="Trouble"></a>Troubleshooting
If, after following the guide, Embedded Windows Media still won't play properly, then recheck that the <a href="#CheckWMP">Windows Media Player plugin files</a> and the <a href="#CheckAX">ActiveX plugin file</a> are installed, and that the issue is not documented in the <a href="#ConfigWMP">Configuring/Troubleshooting the Windows Media Player plugin</a> section.

If you are still unable to resolve any issues, ask for help here in the Mozilla Firefox Support forum. Say that you followed this guide and include the following information:
  • Windows Version
  • Firefox Version
  • Windows Media Player version
  • Difficulties with any of the above steps
  • Whether or not the players on the <a href="#CheckWMP">WMP Test Page</a> and/or the <a href="#TestAX">ActiveX Test Page</a> work
  • A link to a page with embedded media that doesn't work properly (if applicable)
  • Any received error messages (if applicable)
  • If the player loads but doesn't play, right-click on the player. Is 'Properties' greyed out?
  • If the player loads but doesn't play, right-click on the player. Is 'Error Details' greyed out? If not, click on it and supply the information you see.
  • Any other relevant information

keywords: ActiveX Active-X plugin Windows Media Player Mediaplayer WMP 6.4 7 9 10 stream streaming embed embedded embedding video mp3 wmv wma asf asx

Thanks to AnonEmoose for letting me cannibalise his guide, Adam Lock for his ActiveX plugins, Chris Pederick for his User Agent Switcher Extension, _Jim_ for his ActiveX test page, and rtmjr50 for his input and help.