I'm a little surprised that my fresh install of Ubuntu 21.10 can't play .mp4 files. This seems like a rather basic ability. Anyway, after getting very unhelpful errors in VLC, I installed the default GNOME player, totem, which gave me a more helpful error message: The necessary MPEG-4 AAV codec(s) is missing. But I fail to find any helpful info on where to get this. Not even here on askubuntu. What's going on?
01 Answer
When installing Ubuntu, users have the possibility of installing additional third-party drivers, codecs, firmware and other extras:
Codecs can be installed a posteriori if this option isn't selected during the Ubuntu installation.
sudo apt install ubuntu-restricted-extras
