I would like to have a new option in the \includegraphicscommand. The idea ist that there is no error when the file does not exist - maybe just a friendly warning.
Ideally, the file extension is not needed (to be flexible in the future) but if it's needed that's also ok (at the moment it's not necessary).
\documentclass[a4paper,11pt]{article}
\usepackage{graphicx}
\begin{document}
\includegraphics[myDoNotComplainIfFileIsMissing]{MyFileThatMayOrMayNotExist.ext}
\end{document}
\newcommand{\ncigraphics}[1]{\iffileexists{#1}{\includegrapchics{#1}}{}. Unfortunately you have to define the file extension. And you have to add some more magic, to hand over the optional arguments for the includegraphics command. – Jan Jan 29 '17 at 15:33