I've installed the latest version of pgf and tcolorbox but I still get an error :

I do not know the key 'tcb/shadow'...


The following is the first part of the preamble

\documentclass[xcolor=svgnames,a5paper]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}

\usepackage[frenchb]{babel}
\usepackage{multicol}
\usepackage{amssymb,amsmath,amsthm,amsfonts}
\usepackage{cases}
\usepackage[svgnames]{xcolor}
\usepackage{tcolorbox}
\tcbuselibrary{skins}
%\usepackage{tikz}
\usepackage{tkz-tab}
\usepackage{tkz-base}
%\usepackage{tkz-arith}
\usepackage{tkz-fct}
\usepackage{tkz-tukey}
\usepackage{pgfplots}

\usepackage{mdframed, graphicx, xkeyval,ifthen, ifpdf, etoolbox}
\usepackage{tabularx}

\usepackage{pifont}

\usepackage{colortbl}
\usepackage[tikz]{bclogo}

\usepackage{alterqcm}

\usepackage{mdframed, graphicx, xkeyval,ifthen, ifpdf, etoolbox,fp,calc}

\usepackage{fancybox}

\usepackage{framed}
\usepackage[right]{eurosym}
\usepackage{multicol}
\providecommand{\subtitle}[1]{%essai commande de sous-titre
\usepackage{titling}
\posttitle{%
\par\large#1\end{center}}
}

\frenchbsetup{StandardLists=true}
\usepackage{enumitem}
\setlist[itemize,1]{label=$\diamond$}
\setlist[itemize,2]{label=$\bullet$}
\usepackage{fancyhdr}
\pagestyle{fancy}

\usepackage{lmodern}
\usepackage{textcomp} % provides euro and other symbols

\usepackage{hyperref}
\hypersetup{
citecolor=Blue,
urlcolor=Blue,
\urlstyle{same}  % don't use monospace font for urls

\usepackage[margin=2cm]{geometry}


And here is the code for a \newcommand which uses tcolorbox

\newcommand{\imps}[2]{%
\tcbset{skin=enhanced,colback=red!5!white,
colframe=red!75!black,fonttitle=\bfseries}

#2.
\end{tcolorbox}
}


Thanks a lot for your help

TeXwriter 1.6.9 : Android

An error occures using the option "most" or "all" Here is a shorter document to help you.

\documentclass[xcolor=svgnames,a5paper,]{article}
\usepackage[utf8]{inputenc}
\usepackage{pgfplots}

\usepackage{colortbl}

\usepackage{tcolorbox}
\tcbuselibrary{skins}

\definecolor{gris}{gray}{.80}
\newcommand{\imps}[2]{%
\tcbset{skin=enhanced,colback=red!5!white,
colframe=red!75!black,fonttitle=\bfseries}

#2.
\end{tcolorbox}
}
\begin{document}
\imps{4}{L'abscisse figure toujours en première position et l'ordonnée en seconde position}
\end{document}

• Please post a complete document, not only fragments. The package is called tcolorbox, not tcbcolor. The whole preamble is quite messy. Isolating the tcolorbox call it works (apart from the unknown color 'gris') – user31729 Dec 29 '17 at 20:32
• have you tried \usepackage[most]{tcolorbox} or (overkill) \usepackage[all]{tcolorbox}, for example? – cmhughes Dec 29 '17 at 21:19
• @cmhughes: It should work with the skins library already (which is loaded according to the code) – user31729 Dec 29 '17 at 21:21
• @cmhughes yes but it doesn't work. – imotep81 Dec 30 '17 at 6:59
• @ChristianHupfer Thanks for your quick answer I have posted a new shorter document. It doesn't work anymore. – imotep81 Dec 30 '17 at 7:02

Here's an extract from the CHANGELOG file in the sources for tcolorbox:

version 2.31 (2013/06/18)
- several internal changes
[...]
- new shadow features for the 'skins' library with the options:

• In fact I wanted to get a shade effect inside a box of mines. With tikz I get what I wish : \begin{tikzpicture} \node [copy shadow={fill=blue,shadow xshift=0.5ex,shadow yshift=-0.5ex},rounded corners=3pt, shade,top color=green!40 ,draw=blue,thick,text width=#1cm] {#2}; \end{tikzpicture} in the definition of the newcommand \imps – imotep81 Jan 3 '18 at 21:31