Audio playback but no video in Windows Media Player

[Phu]

I'm trying to play a divx movie but I only get audio when I play it in Windows Media Player. It attempts to download a codec, but fails and I get the visualizations. I tried playing it in GDivx Player and Divx Player 2.0 Alpha but neither can play it. Any suggestions on what I should do?

[Enchanter]

Check what codec is needed via Virtualdub's File Information.
1. Open file in Virtualdub
2. Go to File -> File Information. Post what you see here.

[Phu]

Audio but no Video

Ok so I tried to open the file in VirtualDub and it couldn't open it so I never got to go to File Information. But the error message I got I'll type below.
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VirtualDub Error

Couldn't locate decompressor for format 'XVID' (unknown)

VirtualDub requires a Video for Windows (VFW) compatible codec to decompress video. DirectShow codecs, such as those used by Windows Media Player, are not suitable.
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[setarip]

Download and install the XVID codec...