title: What makes a Wordpress theme an "invalid parent theme"?
body: <p>In order to overwrite some CSS of an existing Wordpress theme, I would like to create a child theme of it as described on <a href="http://codex.wordpress.org/Child_Themes#Example_of_a_basic_Child_Theme" rel="noreferrer">http://codex.wordpress.org/Child_Themes#Example_of_a_basic_Child_Theme</a> .</p>
  
  <p>I created a directory along with the style.css file, where the parent theme's name is defined as "template". So far, so good. When I go to the themes page in Wordpress' administration, I get the message "The [name of parent theme] theme is not a valid parent theme.", and I cannot activate it.</p>
  
  <p>I am wondering how Wordpress finds out if a parent theme is valid or not and if there is a way to make the parent theme a valid parent theme.</p>
  
  <p>In order to find out if the defined parent theme is the problem, I replaced the "template" definition with another theme, which is also installed on the same server, and that worked.</p>
  
  <p>Thanks in advance for your help.</p>