Sometimes, the video or audio content in a web page cannot be properly downloaded and displayed in Firefox. A required plugin may be missing, the page may be coded specifically for Internet Explorer, or the content may be blocked for some reason. This article provides some tips to help you solve these problems.

Plugins

Although Firefox can display some media on web pages, such as images, it needs the help of media players and browser plugins for video, audio, and other content. Although you may have the correct media players installed to play video and audio files, you may be missing the necessary plugins when the media is embedded within the web page itself.

The following articles and related notes describe some common plugins, the media types they handle, and how to install or configure them.

• Flash Guide
  • See also: Flash-based videos and sound do not play correctly
• Shockwave Guide
• Windows Media Player Guide
  • The Windows Media Player plugin will only play a specific few Windows media formats (.asf, .asx, .wm, .wma, .wax, .wmv, and .wvx) unless the web page is specifically designed for Firefox and other Mozilla browsers. Internet Explorer will use Windows Media Player for many other formats like mp3 and midi, but Firefox will require another plugin, such as QuickTime. See the Using the Windows Media Player plugin with Firefox article for a more detailed explanation.
• QuickTime Guide
  • The QuickTime plugin can handle many different types of media but may not be configured to handle some common file formats found online, such as .mp3, .midi, .wav, and .mpg. You can select the media formats you want QuickTime to play in Firefox in your QuickTime Preferences. See the QuickTime article for details.
• RealPlayer Guide
  • The RealPlayer 10.5 plugin plays the .rpm format only. Other Real media files (.rm, .ram, .ra) may not work. See the RealPlayer article for more information.
• Java Guide

Other solutions

Some sites with multimedia content may require you to allow popup windows or cookies or that you disable ad-blocking. Try the following:

• Verify that cookies are enabled in the Privacy panel in the OptionsPreferences window. Verify that the site is not blocked in the Cookie Exceptions list.
• You can allow the website as an exception in the Firefox pop-up blocker. The "Block pop-up windows" option is found in the Content panel in the OptionsPreferences window.
• For the time being, you can disable any ad-blocking software or Firefox extensions, such as Adblock or Adblock Plus. If the site works with ad-blocking disabled, you may want to add the site to your whitelist in your adblocker filter.
• Advanced users: If you use a Windows hosts file, you can temporarily disable it by renaming it Xhosts. Or, you can edit the hosts file to remove specific entries such as ad.doubleclick.net that can cause videos on certain sites to fail ( For more information, see the MozillaZine forums). To apply changes to your hosts file, you may need to flush the DNS cache by entering the command
  ipconfig /flushdns
  in the Run dialog box in Windows.

In addition, there may be third-party Firefox extensions that can help you. Go to addons.mozilla.org to search for and install extensions for Firefox.

For more information about add-ons, read Customizing Firefox with add-ons.

Based on information from Video or audio does not play (mozillaZine KB)