Playing mp4 audio gives error message "Video can't be played because the file is corrupt"

Question

Playing a particular mp4 audio file directly from a website link gives error message "Video can't be played because the file is corrupt". However other mp4 audio files from this same website do work correctly. What can I do to get all the the mp4 audio files to play directly from the same website? I must have the correct plugins, etc. since the other files play. This file is not playing from YouTube, is it on the website.
Thank you for your help.

Answer 1

What is the link to the site and file in question?
MP4 files should be handled by Firefox itself, not a plug-in.
# Click the ≡ Menu Button and choose Add-ons.
# Click Plugins.
# Set every plug-in to "Never Activate".
# Try loading the file again. Is there any difference?
You have two versions of Flash Player installed. Perform a clean installation of Flash Player as follows.
# From the following page, save the uninstaller somewhere handy, like the desktop.
#* [http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html#main_Download_the_Adobe_Flash_Player_uninstaller Uninstall Flash Player for Windows | Adobe Support]
# From the following page, save the installer for other browsers. If you also use Flash Player in Internet Explorer, also save the ActiveX version.
#* [http://helpx.adobe.com/flash-player/kb/installation-problems-flash-player-windows.html#main-pars_text_4 Direct downloads of Flash Player for Windows | Adobe Support]
# Exit all applications.
# Run the uninstaller.
# In Windows Explorer, try to open the following folders. If they still exist, delete them manually.
#* <pre>C:\Windows\system32\Macromed\Flash\</pre>
#* <pre>C:\Windows\SysWOW64\Macromed\Flash\</pre>
#* <pre>%AppData%\Adobe\Flash Player\</pre>
#* <pre>%AppData%\Macromedia\Flash Player\</pre>
# Restart your computer.
# Run the installer for other browsers.
# Run the ActiveX installer if you downloaded it.