你可以用VLC    VLC 開到 AVI format file  去看看詳情  http://www.videolan.org/vlc/features.html   
要是想開divx file 可以去 http://www.divx.com/divx/windows/ 裝   DivX Player 即 free download 那個 裝了後 VLC 也可以看divx format file

如不想麻煩 要一次過的software 就用storm codec 吧  內裡 support avi , divx, mpg, RM 等 format  安裝storm codec同時亦裝了 media classc player ... 是跟在prgram 裡的   ...可以去 http://www.free-codecs.com/download/Storm_Codec.htm

you can open it using winamp or jetaudio. that also support .avi movie beside mp3 format.

You can try the player below.  It is also Media Player Classic 6.4.9 but packed with many codecs.

http://yatoshi.com/en/index.php

it is very easy.
First update the newest version of window media player.
if it doesnt work, look for codec for divx and xvid and download it
if it still doesnt open download ac3 filter

去www.webeee.com下kmp播放器,可播放99.9%檔案