Broken wmv9 codec - how to fix?

[katana]

I recently installed a video editing suite on Win XP/SP3.
However shortly after I installed it, I found that Microsoft's Windows Media Player 9 (WMP9) playback of video files became corrupted with some files no longer playing at all (just a black screen with sound), to others with choppy video playback or distorted picture playback.
Uninstalling the offending software made no difference.
I was able to get .avis and some .wmv files to play again by allowing WMP9 to re-download the required codecs and by restoring the registry from an earlier date (I had backed up my registry). However at the moment, WMP9 playback of .wmv files with the 'Windows Media Video 9' (wmv9) codec are corrupted. The picture just plays back with rolling horizontal lines down the screen, although sound is unaffected. The picture looks a bit like that on an old cathode ray tube TV when the vertical hold has gone.
VLC player is able to play these wmv9 files ok though, presumably since it comes with its own codecs.
Also, trying to encode any file to WMV format in TMPGEnc 4.0 Express now fails with the error message 'Falied to obtain the codec information'' (80004002)'.
Uninstalling and reinstalling the 'windows media video 9 vcm codec' from Microsoft via Add/Remove Programs made no difference.
Any ideas on how to fix wmv9 playback?
Thanks in advance for any advice or info.

[admin]

Have you tried to reinstall WMP9?

The way I like to diagnose the problem is to grab GraphEdit and use the "Render Media File" (CTRL-R) function to load the WMV file that won't play properly, and see which codecs are being used. This would at least give you a starting point on knowing which codec to remove from your system.

[katana]

Hi,
Thanks for your reply.
WMP9 doesn't appear in Add/Remove Programs.
There is an option to remove it via Control Panel>Add Remove Programs>Add/Remove Windows Components - but this only gives the option to remove 'access to Windows Media Player from the Start Menu and Desktop', not the program itself.
So perhaps I'll leave WMP9 uninstallation for now.

Going to GraphEdit, here's a screenshot of one of the rendered problematic .wmv files.
I'm not really sure how to interpret it.
Thanks in advance for any suggestions.

[admin]

Rather than uninstall/install, perhaps just a re-install would be okay. I don't suppose you want to upgrade to WMP 11, as I think that will definitely solve this problem (although it might create other problems in the process).

From your GraphEdit screenshot, where it says "AVI Decompressor", it should be showing "WMVideo Decoder DMO" and then connecting straight to the Video Renderer.

So it's the codec "AVI Decompressor" that's fouling things up. What I would do next is to download Codec Tweak Tool and then use the "generate a list of all codecs and filters" option, which then spits out a text file that lists all your installed codecs. Search for the one that says "AVI Decompressor" (there might be more than one, since on your screenshot, it says "AVI Decompressor 0001"), there should be an .ax file attached to it, and you can then unregister the filter(s) using these commands:

1. Press Start button
2. Select Run
3. Type in the following and press enter:

regsvr32 /u "path\to\filename.ax"