The easiest solution i can suggest is to follow the link below and download the codec pack, from the downloads section.

http://nimo.titanesk.com/

The codec pack is a collection of lots of different audio and video codecs and directshow filters that are used to play various types of avi files including DivX in windows media player.

I used this tool some time back...and it resolved the codedc issues i was having.

Please make sure you read their faq section for more guidance.

I hope the above is of some help.

Valenuk1