How to play MKV files on Peppermint Linux

Now I have to give a big shout out and thank you to ConfigX, from the Peppermint forum.

This type of file is a container and a special codec is needed to read it.

Open a Terminal window, click Menu >> Accessories >> Terminal
Type in:
sudo apt-get install lubuntu-restricted-extras
Press <ENTER>
Type in your sudo password and press <ENTER>

Now when trying to play MKV files with VLC, it will work.