Install Shak007 codec releases. both 32bit
Suggested changes from default . . .
Open the 32bit settings app
Help TAB, choose to associate filetypes to WMP
H264 TAB, choose the Divx codec
settings Just for you, in the x64 settings app (for Media Center)
go to the SWAP TAB, choose to disable the Microsoft Video codec, and the DMO codecs.
If you would prefer FFDshow to handle MP3 audio (alot of AVI's use this) make that selection also
If you want the same behavior from 32bit players, make the above changes in the 32bit app too.