I'm running Windows 7 x64 and couldn't play the sound in an .avi video file in the venerable VLC media player in the "vo3+" format. I downloaded Media Player Classic Home Cinema and see if it would work with that and got a similar problem, and the diagnostics screen that comes up shows:
majortype: MEDIATYPE_Video"73647561-0000-0010-8000-00AA00389B71" subtype: Unknown GUID Name "00006771-0000-0010-8000-00AA00389B71"
After doing some research it seemed that I needed the OGG Vorbis ACM codec. So I downloaded it and right clicked on the file "vorbisacm.inf" and picked install but still same problem with Windows.
It turns out that in 64bit Windows you have to do a bit more to get the OGG Vorbis ACM installed correctly:
1)unzip/unrar the Ogg Vorbis codec compressed package into somewhere like "c:\ogg_vorbis"
2)Run cmd.exe with administrator rights. Find "cmd.exe" and then right-click on it and select "Run as administrator".
3)in the CMD window, type "cd %windir%\SysWOW64" and hit ENTER
4)type "rundll32 setupapi.dll,InstallHinfSection DefaultInstall 0 C:\ogg_vorbis\vorbisacm.inf" and hit ENTER
Voila- the file will now play with sound under Media Player Classic. Unfortunately I tried VLC and it still showed the vo3+ error:
No suitable decoder module:
VLC does not support the audio or video format "vo3+". Unfortunately there is no way for you to fix this.