\documentclass{article}
\usepackage{hyperref}

% For missing package error
%\usepackage{testpackage}

\begin{document}
This test document reproduces the errors and warnings listed here:
\url{http://en.wikibooks.org/wiki/LaTeX/Errors_and_Warnings}

\date

\test{}

{Hello world!}}

\epsilon

Hello world!
\\

Thistestdocumentreproducestheerrorsandwarningslistedherethistestdocumentreproducestheerrorsandwarningslistedhere

\section{$\alpha$}

\end{document}