# “Sorry, but MiKTeX Compiler Driver did not succeed” error when compiling

For some reason, my code will only run when it contains certain lines in

\documentclass[11pt,a4paper]{report}
\usepackage{amsthm}
\input{projdefs}
\begin{document}

\begin{defn} In the case of the graph $C_3$ above, the polynomials generated
would be
$[x_1^3-1=0,x_2^3-1=0,x_3^3- 1=0,x_1^2+x_1x_2+x_2^2=0,x_2^2+x_2x_3+x_3^2=0,x_1^2+x_1x_3+x_3^2=0].$
\end{defn}

\end{document}


I would like to take out the defn part, but then I receive the message

Sorry, but "MiKTeX Compiler Driver" did not succeed.

Incidentally I don't have any references to these lines further on, they should be totally independent of the rest of the document

• We can't analyse the problem only with the small snippet of code you provided. You'll have to provide more in the form of a minimal, working example (MWE). It should start with \documentclass and end with \end{document}. – Werner Dec 13 '18 at 1:26
• Sorry about that, added some code to the original post – Mitch Dec 13 '18 at 1:36
• projdefs is not part of TeX Live. To me your issue sounds like a faulty MikTeX installation. – Henri Menke Dec 13 '18 at 1:43

projdefs is not part of any installation - it is a local file. It seems that \newtheorem{defn}{Definition}[section] (or something similar) must be defined in that file, because the defn environment is not defined by amsthm package that I can find through a cursory search. Commenting out the \input{...} line and using \newtheorem, this MWE compiles without warnings/errors on my MiKTeX installation.

As far as fixing your error, it appears that MiKTeX is attempting to write (or write to) the PDF file, but failing. Do you have the PDF file open using another program? (I get errors if, for example, I have the PDF open in Adobe Acrobat, forgot to close it, and attempt to compile my document again.) If closing a PDF reader doesn't work or isn't applicable, it sounds likely that one of the build files or display files became corrupt.

Try deleting these files:

[filename].synctex.gz
[filename].pdf
[filename].aux
[filename].log


And recompile again.