# Why do I get a black rectangle instead of my external picture?

I write some of my network notes in TeX. I wanted to make a table, and inside it insert an image:

.

I wrote a document:

\documentclass{article}
\usepackage[demo]{graphicx}
\usepackage{booktabs}
\usepackage{array}

\begin{document}
\begin{tabular}{m{3cm}m{3cm}m{5cm}}
\toprule
Configuration for ... & Commands & Topology\\
\midrule
PPP: CHAP, PAP & \#sh int se 0/0/0  & \includegraphics[width=4cm, height=4cm]{chappap.png}\\
& & \\
\bottomrule
\end{tabular}
\end{document}


But instead of my network topology image, I see only this: .

I don't know what is wrong, cause my image is 100% in the same dir, as my *.tex file.

EDIT:

Changed my code as @Jubobs suggsted, no everything is just fine:

\documentclass{article}
\usepackage{graphicx}
\usepackage{booktabs}
\usepackage{array}

\begin{document}
\begin{tabular}{m{3cm}m{3cm}m{5cm}}
\toprule
Configuration for ... & Commands & Topology\\
\midrule
PPP: CHAP, PAP & \#sh int se 0/0/0  & \includegraphics[width=4cm, height=4cm]{chappap.png}\\
& & \\
\bottomrule
\end{tabular}
\end{document}

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That's what happens when the demo option is passed to the graphicx package: all external pictures are replaced by black rectangles. Do you also get the black rectangle without that option? –  Jubobs May 4 '13 at 20:00
@Jubobs: Geez, didnt think about that it can be 'the problem' here. Thanks :D –  Katie May 4 '13 at 20:03
@Katie If you're happy with it, could you please accept my answer? That will reduce the clutter in the "unanswered" section of the site :) –  Jubobs May 5 '13 at 12:24
@Jubobs: Sorry that made it so late but done! Accepted your answer, thanks again;) –  Katie May 5 '13 at 15:24

That's what happens when the demo option is passed to the graphicx package (as in your MWE). That option is described in the graphicx manual:

demo: Instead of inserting an image file \includegraphics draws a 150 pt by 100 pt rectangle unless other dimensions are specified manually.

If you want the actual external picture to be included by \includegraphics{...},

1. disable the demo option,
2. make sure that the path to that picture specified in \includegraphics{...} is correct.

Note that you will get an error from LaTeX, not merely a black rectangle, if the path to your external picture is incorrect.

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