Suddenly error:

user warning: Smarty error: unable to read resource: "themes/three_goats_on_a_highway/button.tpl" in /var/www/themes/engines/smarty/libs/Smarty.class.php on line 1093.

There was no button.tpl in my theme folder.

So I created one. The buttons were gone.
I deleted it and the template cache in templates_c/ folder as well.

The error jumps back in.

So, what to do? How can I write a button.tpl file or get rid of this error? I need my Preview and Save buttons!!