|As Daveincaps already replied: is your computer running Windows ME?|
If not you have posted in the wrong forum.
If you do have Windows ME, you can try the K-Lite codec pack (version 2.8 seems to work on ME) to play almost any movie you like.
You should also mention your hardware specifications when asking such a question (how much RAM, what processor etc.) and finally you should try a new (clean) installation in case your computer is infected with some kind of virus or malware.
If you use a (clean) ME computer that has never been connected to the internet and if you are sure your USB stick/drive is not infected, with the right hardware specifications you should be able to play almost any kind of movie with Mediaplayer and K-Lite......
message edited by Soedesh