Matroska! Wave off the future!
BS!
I have yet to have a single .mkv file EVER open with VLC. In fact, I have yet to have ANY program open a .mkv file. VLC says .mkv it is supported. VLC says there is a codec for .mkv files. Then why can't I get the things to open?
Is there a secret mantra one needs to chant? "You f---ing piece of s---!" has yet to work for me and I say it a lot when I am trying to open one of these files. Hasn't worked yet.
Any help out there?