For those of you who have DVD players on your computer and are having trouble playing them, you may find that there is a problem with your DVD decoder. If it is out of date or incompatible with your DVD Drive, you may be experiencing difficulty. In order to find out what codec you have, if any at all, you should try these easy steps:

1.) Go to “Start–>Run” and then type “cmd” in the box that opens.
2.) Click “Ok” and you should see a new command prompt window open.
3.) In this new prompt, type the following: “dvdupgrd /detect” (with a space between “dvdupgrd” and the “/”)
4.) Hit enter and a new window should pop up providing the name and version of your DVD codec.

Now you can go on Google or any other search engine and type in your codec name to find information on common problems with it. Note that this has only been tested on Windows XP and may not work on 98 or 2000.