# Overleaf compile Error

I'm new with LaTeX and Overleaf and I'm getting a compile error without error message while compiling the following code:

\documentclass[a4paper, oneside]{scrbook}
\usepackage[clearempty]{titlesec}
\usepackage[section]{placeins}
\usepackage{tabularx}
\usepackage{pdfpages}

\usepackage[ngerman]{babel}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{graphicx}
\usepackage[colorinlistoftodos]{todonotes}

\usepackage{glossaries}
\setacronymstyle{long-short}
\newacronym{ics}{ICS}{Ice Cream Sandwich}

\usepackage[
backend=biber,
style=authoryear-icomp,
firstinits=true,
isbn=false,
pagetracker=true,
maxbibnames=50,
maxcitenames=2,
autocite=inline,
block=space,
backref=true,
backrefstyle=three+,
date=short,
url=false,
doi=false,
eprint=false,
isbn=false
]{biblatex}

\usepackage[german]{cleveref}
\usepackage{csquotes}

\title{example1}

\author{Simon Beyer}

\date{\today}

\begin{document}

\begin{titlepage}

\vspace*{2cm}

\begin{center} \large

{\huge example}

\end{center}
\end{titlepage}

%\setcounter{page}{1}
\tableofcontents

\chapter{example1}

\section{example2}
\section{example3}

\end{document}


There are two things causing errors:

1. In the center environment you have an opening brace ({) without a closing brace. As it stands, you can just remove that brace.

2. titlesec is apparently not compatible with the KOMA-classes. I don't know if there is a way to use both, but the simplest solutions is either

1. Remove \usepackage[clearempty]{titlesec}, or

2. Use book instead of scrbook.

In addition, Overleaf doesn't seem to be able to deal with biblatex. Removing that package, and it compiles fine. This is a bit strange, considering that biblatex isn't used at all, and there are no errors in the .log file or the .blg file. I have no idea what's going on, at the moment. Even this minimal file makes Overleaf throw an error, even though there is no actual error:

\documentclass{article}
\usepackage{biblatex}
\begin{document}
abc
\end{document}


• @Rastaman For some reason biblatex causes Overleaf to choke. I have no idea why, it works fine when compiling locally, and the log from Overleaf also says that three pages of PDF output was written. At the moment, since you're not using biblatex, remove it. Later, when you add a bib-file and citations, see if works then. – Torbjørn T. Apr 27 '16 at 11:27
• after removing biblatex I get the following error message: ./main.aux:4: Undefined control sequence. l.4 \abx@aux@sortscheme EDIT: after recompiling it works! thanks – Rod Kimble Apr 27 '16 at 11:38
• @Rastaman Yes, the \abx.. macro is defined by biblatex, and is written to the .aux file, an auxiliary file that is read at the start of a compilation, and rewritten during it. So the first time compiling, that macro is still there and unknown, since biblatex is gone, but the next time the .aux file has been recreated, and that macro is gone, so it works. – Torbjørn T. Apr 27 '16 at 11:45
• @TorbjørnT. Right now what happens is that if biblatex is loaded but there is no \cite command, latexmk chokes with biber test: failed to create output file. (I've just got your message to Overleaf support and forwarded to our engineers) – LianTze Lim Apr 27 '16 at 13:11