title: Gtk-Message: Failed to load module “pantheon-filechooser-module”
body: <p>I am a green hand on Linux and am now on Elementary OS Loki.
  I met a problem when I tried to access to Software Sources with the command line: </p>
  
  <pre><code>gksudo software-properties-gtk
  </code></pre>
  
  <p>This is what I received:</p>
  
  <pre><code>&gt; Gtk-Message: Failed to load module "pantheon-filechooser-module"
  &gt; (gksudo:21308): Gtk-WARNING **: Unable to locate theme engine in
  &gt; module_path: "pixmap", (gksudo:21308): Gtk-WARNING **: Unable to
  &gt; locate theme engine in module_path: "pixmap", (gksudo:21308):
  &gt; Gtk-WARNING **: Unable to locate theme engine in module_path:
  &gt; "pixmap", (gksudo:21308): Gtk-WARNING **: Unable to locate theme
  &gt; engine in module_path: "pixmap",
  </code></pre>
  
  <p>Just to be more specific, this problem happened after I made an <code>autoremove</code>. I think probably I have wrongly deleted some package useful.</p>
  
  <p>All answers will be appricated, thanks in advance.</p>