I have a problem compiling an article using natbib. I am using WinEdt to compile, for example this what I found online:

\begin{filecontents*}{bibtest.bib}
@book{goossens93,
author = "Michel Goossens and Frank Mittlebach and Alexander Samarin",
title = "The Latex Companion",
year = "1993",
}
\end{filecontents*}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\documentclass{book}
\usepackage{natbib}

\begin{document}
\cite{goossens93}

\bibliographystyle{plain}
\bibliography{bibtest}

\end{document}


I do:

Shift+Ctrl+L (latex)

Shift+Ctrl+L (latex)

Shift+Ctrl+B (bibtex)

Shift+Ctrl+L (latex)

Shift+Ctrl+L (latex)

and finally

Shift+Ctrl+D (dvips), pspdf

And in the pdf I don't get the name of the cited authors but I get instead: (?)

Also I get an error when I do Shift+Ctrl+L:

I do not know how to fix that because natbib.sty is in the folder: *\MiKTeX 2.9\tex\latex\natbib