# No diagrams appear with feynmp-auto

I get blank space and no diagrams with the following code working in Texmaker on Windows. The mp file has been created. I have run pdflatex command. The log file gives the version as pdfTeX, Version 3.14159265-2.6-1.40.18 (MiKTeX 2.9.6500 64-bit) (preloaded format=pdflatex 2017.11.7) Any help would be much appreciated:)

     \documentclass{article}
\usepackage{feynmp-auto}
\begin{document}
\begin{fmffile}{simple_labels}
\begin{fmfgraph*}(40,25)
\fmfleft{i1,i2}
\fmfright{o1,o2}
\fmflabel{$e^-$}{i1}
\fmflabel{$e^+$}{i2}
\fmflabel{$e^+,\mu^+$}{o1}
\fmflabel{$e^-,\mu^-$}{o2}
\fmflabel{$i\sqrt{\alpha}$}{v1}
\fmflabel{$i\sqrt{\alpha}$}{v2}
\fmf{fermion}{i1,v1,i2}
\fmf{fermion}{o1,v2,o2}
\fmf{photon,label=$\gamma,,Z^0$}{v1,v2}
\end{fmfgraph*}
\end{fmffile}
\end{document}

• Unfortunately, the automatic feature of feynmp-auto mo longer works because Metapost has been withdrawn from the list of programs allowed to be called in the testricted shell escape, so one needs to activate -shell-escape for the automatic call. – egreg Apr 8 '18 at 7:38

I could make it work by adding the force option and after compiling twice with pdflatex -shell-escape.

 \documentclass{article}
\begin{document}
\begin{fmffile}{simple_labels}
\begin{fmfgraph*}(40,25)
\fmfleft{i1,i2}
\fmfright{o1,o2}
\fmflabel{$e^-$}{i1}
\fmflabel{$e^+$}{i2}
\fmflabel{$e^+,\mu^+$}{o1}
\fmflabel{$e^-,\mu^-$}{o2}
\fmflabel{$i\sqrt{\alpha}$}{v1}
\fmflabel{$i\sqrt{\alpha}$}{v2}
\fmf{fermion}{i1,v1,i2}
\fmf{fermion}{o1,v2,o2}
\fmf{photon,label=$\gamma,,Z^0$}{v1,v2}
\end{fmfgraph*}
\end{fmffile}
\end{document}