Have you uncompressed the video file? Make sure you do that, and then, save the actual video to your Divx Movie folder, for some reason Divx wont let you go into any subfolders when trying to look for a video. It tries to play an acutual folder, weird. But all you have to do is,

1.] Find Divx Movie folder (should be on desktop if you made a shortcut)

2.]Find your ACTUAL VIDEO and move or copy it to the Divx Movie folder.

3.] Start up the Divx movie player and then look for a button that looks like an eject symbol, press that and then locate your Divx movie folder and it should start.

If that dosent work, then Im sorry, Im pretty much at of my realm at this point. Im sure that the mods gets this alot, they will probably help out.