
\documentclass{article}%
\usepackage[tex4ht]{hyperref}
\begin{document}

\begin{equation}
\label{greatprop}
a = b
\end{equation}

This is a text and there is a label.

\section{this is the problem \ref{greatprop} \label{alabel}}

possible solutions:

\begin{itemize}
 \item remove the label in the section-command
 \item do not use hyperref-package
 \item remove the ref in the section-command
\end{itemize}

\end{document}