The LyX-made file has errors. I have MiKTeX2.7 .
How could I resolve these?
The LyX source is
% Preview source code
%% LyX 1.5.2 created this file. For more info, see http://www.lyx.org/.
%% Do not edit unless you really know what you are doing.
\makeatletter
[EMAIL PROTECTED]"C:/Documents and Settings/Sandor/My
Documents/\string"/}}
\makeatother
\documentclass[oneside,english]{amsbook}
\usepackage[T1]{fontenc}
\usepackage[latin9]{inputenc}
\makeatletter
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Textclass specific LaTeX commands.
\numberwithin{section}{chapter}
\numberwithin{equation}{section} %% Comment out for sequentially-numbered
\numberwithin{figure}{section} %% Comment out for sequentially-numbered
\theoremstyle{plain}
\newtheorem{lem}[thm]{Lemma}
\usepackage{babel}
\makeatother
\begin{document}
\chapter{nmmm}
\begin{lem}
kkk
\end{lem}
\end{document}
---------------------------------
The error messages are
LaTeX Error: No counter 'thm' defined.
\newtheorem{lem}[thm]{Lemma}
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
.................
LaTeX Error: Environment lem undefined.
\begin{lem}
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
........................................
LaTeX Error: \begin{document} ended by \end{lem}.
\end{lem}
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
