I have just installed a font called "28 Days Later" from www.1001freefonts.com but now I have a problem because the following code snippet does not compile, it produces some errors, roughly saying that "The 28 Days Later font could not be found.".
\documentclass[preview,border=12pt,12pt,varwidth]{standalone}
\usepackage{fontspec}
\setmainfont{28 Days Later}
\begin{document}
Oh my ghost
\end{document}
So, how do we know the correct name for an installed font to be passed as the argument of \setmainfont?

28 Days Later.ttf, but not with some other arbitrary one – Feb 15 '15 at 08:05lualatexfails too – Feb 15 '15 at 12:43