On Wed, May 07, 2014 at 11:19:07PM +0200, Martin Schöön wrote:
> Quick up-date before bed-time: I commented out the (add-to-list
> 'org-latex-classes stuff
> and restarted emacs: No rerror message and still no org-latex-classes
> variable found
> when trying out C-h v org-latex-classes.

I have a feeling you are a victim of the infamous mixed install issue.

<http://orgmode.org/worg/org-faq.html#mixed-install>

--
Suvayu