I have spent a lot of time trying to make TikZ externalize work (on MiKTeX2.9). So I tried to just run the first program using externalize from the TikZ PGF manual:
\documentclass{article}
% main document, called main.tex
\usepackage{tikz}
\usetikzlibrary{external}
\tikzexternalize % activate!
\begin{document}
\begin{tikzpicture}
\node {root}
child {node {left}}
child {node {right}
child {node {child}}
child {node {child}}
};
\end{tikzpicture}
A simple image is \tikz \fill (0,0) circle(5pt);.
\end{document}
It runs perfectly and produces a pdf and opens the pdf (as my WinEdt 10.1 is configured to do) if I cut out the two lines
\usetikzlibrary{external} \tikzexternalize % activate!
But with those two it generates
! Package tikz Error: Sorry, the system call 'pdflatex -halt-on-error -interact ion=batchmode -jobname "MWE-figure0" "\def\tikzexternalrealjob{MWE}\input{MWE}" ' did NOT result in a usable output file 'MWE-figure0' (expected one of .pdf:.j pg:.jpeg:.png:). Please verify that you have enabled system calls. For pdflatex , this is 'pdflatex -shell-escape'. Sometimes it is also named 'write 18' or so mething like that. Or maybe the command simply failed? Error messages can be fo und in 'MWE-figure0.log'. If you continue now, I'll try to typeset the picture.
Is this a real problem? And if so, how can I avoid it?
It seems to be a real problem. When I continue (by entering q) then it actually does produce a pdf but does not open it. And it reports
Sorry, but texify.exe did not succeed.
I am not able to make externalize work after that. But I do not know what other mistakes I might be making. And I do not want to explore those any further until I understand this one.