Updating packages in TeXLive 2011

Question

I have TeXLive 2011 distribution on my Windows 7. I haven't updated it before. I downloaded it as an iso file. Anyway, I tried to use the mdframed package in an example document like below:

\documentclass{article}

\usepackage{mdframed}
\usepackage{xcolor}
\surroundwithmdframed[
    hidealllines=true,
    backgroundcolor=black!20,
    skipbelow=\baselineskip,
    skipabove=\baselineskip
]{equation}

\begin{document}
Text
\begin{equation}
1+1=2
\end{equation}
Text
\end{document}

But I got the message:

! Undefined control sequence. 

As I've asked it means possibly my mdframed package is not updated.
What should I do? I need to use the mdframed package.

Answer 1

You cannot update TeX Live 2011 since all mirrors are set to update the 2012 version of TeX Live. There is unfortunately not enough man power to support more than one TeX Live.

I suggest you install TeX Live 2012 but be aware that there is also no upgrade routine from the 2011 edition to TeX Live 2012.

Alternatively you might manually update the mdframed package but as it might require other packages to be updated installing TeX Live 2012 might be the easier solution.

Answer 2

To update just one package (mdframed in your case) of the TeX Live, use the following command:

tlmgr update mdframed