# Too many math alphabets used in version normal error when using chemmacros package [closed]

When I load package chemmacros, suddenly the following error occurs:

Too many math alphabets used in version normal.


I've already made sure that I've updated my MikTeX distribution.

Edit: my code is

\documentclass[english,fontsize=11pt,paper=a4,twoside,openright,titlepage,numbers=noenddot,headinclude,BCOR=5mm,footinclude=true,cleardoublepage=empty]{scrreprt}
\usepackage[T1]{fontenc}
\usepackage[latin9]{inputenc}
\setcounter{tocdepth}{3}
\usepackage{amsmath}
\usepackage{amssymb}

\makeatletter
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Textclass specific LaTeX commands.
% Classic Thesis Style loader
\makeatother
\input{classicthesis-config.tex}
\makeatletter
% use Latin Modern instead of Computer Modern sans serif
\renewcommand{\sfdefault}{lmss}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% User specified LaTeX commands.
\usepackage[minionint]{MinionPro}
\usepackage{chemmacros}

\makeatother

\usepackage{babel}
\begin{document}
$-\frac{\hbar^{2}}{2m_{e}}\underset{i}{\sum}\nabla_{i}^{2}$

\end{document}


, whereby the "classicthesis-config.tex" is the same one as the one in https://code.google.com/p/classicthesis (LyX version).

What should I do to repair this problem?

By the way, if I replace the \hbar with \alpha, the problem disappears. The problem still remains if I replace \hbar with \hslash.

-
Please add a minimal working example (MWE) that illustrates your problem. It will be much easier for us to reproduce your situation and find out what the issue is when we see compilable code, starting with \documentclass{...} and ending with \end{document}. – Marco Daniel Mar 10 at 16:53
At least related: “Too many math alphabets” error – cgnieder Mar 10 at 16:59
Your exampel produces ! LaTeX Error: \usepackage before \documentclass. – David Carlisle Mar 10 at 21:15
Ah, I made a mistake when copying the code to the forum. I've edited the code. I also add more description there. – user26939 Mar 11 at 5:18
The problem is almost surely in the MinionPro package that's not generally available. – egreg Mar 11 at 10:26
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## closed as too localized by lockstep, Kurt, Claudio Fiandrino, Stefan Kottwitz♦Apr 11 at 13:01

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