If you try to view a video in Windows media player you can run into a few common problems.
The video doesn’t play at all.
You can see the video but not hear any sound.
You can hear the video but not see it.

In most of the cases the problem is that you don’t have the correct codec installed on your computer. Not all video files are the same, especially those with a .avi extension. A codec is a special bit of software that tells your computer how to play a video file.

The easiest solution is to use another video player. I recommend VLC media player which you can download here. There’s no spyware or anything like that and it can play just about any type of file you throw at it.