I'm not sure it'll help, but look for Nimo on yahoo..
and for me when I've divx installed (without running it) then avi files are opened fine by wmp..
try..
<edit> read:
DivX codec v5.05
Installation
To play DivX movies you first need to install the DivX codec on your computer. The DivX codec v5.05 is the latest version of the DivX codec and it's fully backwards compatible with all previous versions of the DivX codec. To install the DivX codec v5.05 for Windows, follow these easy steps:
1) Download the right DivX codec for your os
Windows(3.2MB),
Mac(1.7MB) or
Linux(256KB).
2) Double-click on the downloaded file to start the installation
3) Follow the instructions in the installation program
After you've installed the DivX codec v5.05 on your computer, Windows Media Player will be able to play all versions of DivX movies (DivX v3.x, DivX v4.x, DivX v5.x). If you run into any problems, please refer to the
DivX FAQ for solutions to common DivX codec installation and playback problems.
If you're having problems and wish to try a quick solution, download
This Codec. Please note that there's no need to install this version of the DivX codec if you've already got the DivX codec v5.05 installed on your computer as it is fully backwards compatible. However, if you for some reason are having problems with the new codec you could try this codec and see if it works better.