MiKTeX can't write on pdf file

Question

I am using MiKTeX 2.9 on Windows 7.

I'm getting the error: "can't write on pdf file." The pdf doesn't reflect what I wrote. What did I do wrong?

My input:

\documentclass[12pt]{article}
\usepackage{epsf}
\usepackage{amssymb}
\usepackage{graphicx}
\usepackage{setspace}
\usepackage{amsmath}
\usepackage{rotate}
\usepackage{endnotes}
%\usepackage{harvard}
\usepackage{vmargin}
\usepackage[nolists,noheads,tablesfirst,nomarkers]{endfloat}
\usepackage{natbib}
\bibliographystyle{apsr}

\oddsidemargin=1.0in\evensidemargin=0.in
\textheight=8.5in\textwidth=6.6 in \baselineskip=18pt \parskip=6pt

\begin{document}  % added, was missing

TEXT

\newpage \baselineskip=12pt
\doublespacing

\bibliographystyle{apsa}
\bibliography{Dissertation_Proposal}


\end{document}

Answer 1

The error message is generated by the prompt_file_name procedure in TeX.

Most likely causes:

• The output PDF file already exists and is locked by another application, e.g. Adobe Reader (on Windows).

  • In this case, one can usually close the open document (or close the PDF viewer entirely), retype the output file name in TeX's prompt, and press ENTER to try again.
  • If this doesn't work, try deleting the PDF file in Windows Explorer, and hopefully it will tell you what application is the culprit.
  • You could also try a tool like Unlocker.

  (If you are interested in finding a PDF viewer that does not lock open documents, see this related question on superuser.)

• Insufficient hard disk space.

• Insufficient memory. See https://tex.stackexchange.com/a/16901/17427

• Trying to write to a directory that doesn't exist. (This is more likely if you are writing external files through something like tikzexternalize, rather than for the main document output file)^*.

• Trying to write in a protected/unsafe location. See for example https://texfaq.org/FAQ-includeother and https://tex.stackexchange.com/a/2214/17427

A couple of things to note:

• One cannot type x at this prompt to abort. That will write on a file called x.pdf.
• In pdflatex, pressing ENTER without retyping the filename unhelpfully writes on a file called .pdf.
• In lualatex, pressing ENTER without retyping the filename prompts again.
• In xelatex, this prompt doesn't occur. Instead, one seems to get the message ** ERROR ** Unable to open ... and then it exits.

_{^{*Thanks to Sextus Empiricus for pointing this one out.}}