Just installed Kdenlive 0.8.2 on Ubuntu 11.10. Originally I had 0.8.0 from Ubuntu. Then I uninstalled this and reinstalled from the sunab ppa. It would not start, so then I upgraded MLT 0.7.4 to 0.7.6 from Synaptic. Everything seems to work well, but when I go to render in H264 I get error message "Unsupported video codec: libx264". In the Config wizard, this codec is shown as supported? Any ideas.
Best Regards

Try deleting the kdenliverc file in ~/.kde/share/config then restarting kdenlive. I had a similar problem where the h264 encoding options were visible but unusable with a big red 'X' next to them.

I deleted the file, the program started up again and went through the Config Wizard. I still get the same error message "Unsupported video codec: libx264". Thanks for your help. Reading through the various posts maybe I have to reload FFMPEG??
Regards

you have to be using the ffmpeg ubuntu repo's and also did you ensure you did this: To have all codecs activated for project rendering : sudo apt-get install libavcodec-extra-*

Great thanks for your advice. I did what you recommended. The following happened:

libavcodec53 & libavutil51 removed
libavcodec-extra-53 & libavutil-extra-51 & libopenjpeg2 & libvo-aacenc0 & libvo-amrmbenc0 & libxvidcore4 added

Then I removed kdenliverc as suggested by Yellow, restarted and all the rendering options seem to show up now!

Many thanks.
Regards.