VLC does not support the audio or video format "undf".

[RyerAcademy]

I have successfully recorded some video through VideoLAN, but when I go to play the video is gives me this error message:

No suitable decoder module:
VLC does not support the audio or video format "undf". Unfortunately there is no way for you to fix this.

Please advise as to what I can do? Thank you in advance.

Respectfully,
Joshua Ryer

[Rémi Denis-Courmont]

Unknown codec. The codec needs to be defined in the demuxer plugin.

[RyerAcademy]

Where or how do I define that? I'm brand new to all of this.

[Jean-Baptiste Kempf]

Please share the video.

[Telegram Sam]

I saved to my hard disc a track from YouTube. It is listed as .xspf but when I try to play it in VLC 2.0.2 I get the same message as in this thread - that VLC does not support undf. Is there a solution - or generally a way in which to download something from YouTube and listen (and / or view) using VLC? Do I need to convert the file and if so can someone recommend a suitable converter? I am running Windows XP. Thanks.

[Jean-Baptiste Kempf]

undf means undefined. So, every time, we need to have access to the file.

[Jimmer33]

I had the same case with a video from youtube that I was trying to download using IE9 and a known download manager which saved the file as .flv.
However, I tried with Firefox's add-on Download Helper, and it saved the file as .mp4 and it opened successfully.
Donno if it makes sense though...coz prior to using Firefox I tried converting the flv to another format after downloading it but got an error.