With CodecInstaller you'll solve this usual problem immediately, because it will detect codecs installed in your computer and those you need to play your multimedia files.
It includes three main options easily accessible from the interface: installed codecs which will show you installed codecs. ’Analize video’ to guess the codec you need to play it, and 'install codecs' a link for downloading latest news from the Official website.
If you have CodecInstaller in your computer, you have all you need to view your multimedia files.
It needs Microsoft .NET FrameWork 1.1 or higher.