Wordpress: Child-Theme Mystile Child Theme The parent theme is missing. Please install the "Mystile" parent theme.

Template name is case sensitive. The name should according to the folder name.
/*
Theme Name: Mystile Child Theme
Theme URI: http://www.woothemes.com/
Version: 1.3.0
Description: Designed by <a href="http://www.woothemes.com">WooThemes</a>.
Author: WooThemes
Author URI: http://www.woothemes.com
Tags: woothemes
Template: Mystile

Copyright: (c) 2009-2011 WooThemes.
License: GNU General Public License v2.0
License URI: http://www.gnu.org/licenses/gpl-2.0.html

*/

@import url('../Mystile/style.css');

Problem was I had Mystile where it should be: Template: mystile