Undefined control sequence at first line of a document

Question

\documentclass{book}

\usepackage{amsmath}
\usepackage[german]{babel}
\usepackage{amssymb}
\usepackage{amsxtra}
\usepackage[dvips]{epsfig,psfrag}
\usepackage{listings}

\newcommand{\refchapter}[1]{Kapitel~\ref{#1}}
\newcommand{\refsec}[1]{Sektion~\ref{#1}}
\newcommand{\refeqn}[1]{Gleichung~(\ref{#1})}
\newcommand{\reffig}[1]{Abbildung~\ref{#1}}

\title{\bf Grundz\"uge der Softwareentwicklung \\
{\small Analyse- und Entwurfsdokument} \vspace{1cm}\\
\centering
\epsfig{file=figures/logo.eps,width=.4\textwidth}
}

\author{Uschi Musterfrau, Detlef Mustermann und Ralf Auchmustermann}
\date{Matr.-Nr. 0815, 0816 und 0817 \\
email: {\tt [uschi|detlef|ralf]@rwth-aachen.de} 
}

\begin{document}

\lstloadlanguages{[ISO]C++}
\lstset{basicstyle=\small, numbers=left, numberstyle=\footnotesize,
  stepnumber=1, numbersep=5pt, breaklines=true, escapeinside={/*@}{@*/}}


\pagestyle{headings}

\maketitle

\tableofcontents

\include{vorwort}
\include{analyse}
\include{entwurf}
\include{nutzerdoc}
\include{entwicklerdoc}

\bibliographystyle{plain}
\bibliography{analyse_entwurf}

\appendix

\include{quellcode}


\end{document}

this is how my file starts. I didn't even edit it, I received it like this. However, if I want to make a pdf, it gives me the undefined control sequence error at the first line... What is wrong??

Answer 1

It might be that one of the tools in your tool chain gets irritated by a Byte-Order Mark (BOM), which is a special Unicode character to indicate the endianness used in your file.

Unfortunately, a BOM may have unwanted side-effects.

You might try to save the file with another editor which won't add this mark in the beginning, or remove it with a hex editor.

Answer 2

try getting rid of \usepackage[dvips]{epsfig,psfrag} if you're using pdflatex.

Answer 3

Perhaps TeXshop doesn't recognize your file as a LaTeX file and runs it with plain TeX or ConTeXt. If you can post your logfile (the beginning) here, we can help you for sure.

Answer 4

My guess is that you're trying to use TeX instead of LaTeX. TeX won't recognize the \documentclass command. Make sure you use LaTeX.