# Solving the *tex error “I can’t find file pgflibrarytikzpositioning.code.tex”

Basically it means your PGF installation is waaay old. Like from 2007 if you run Ubuntu 8.04 as I happen to. If you want to find out what your version is compile this short tex file:

\listfiles
\documentclass[]{article}
\usepackage{tikz}
%\usetikzlibrary{positioning}
\begin{document}
a
\end{document}

`

After that grab a fresh copy from http://sourceforge.net/projects/pgf/. As root remove (or back up somewhere else) /usr/share/texmf/tex/context/pgf , /usr/share/texmf/tex/generic/pgf , /usr/share/texmf/tex/latex/pgf and /usr/share/texmf/tex/plain/pgf. Extract the new pgf and copy the corresponding folders to the same places, run (as root) mktexlsr and you are done.