Rules / Build

Font not installed

A font requested with fontspec (or a font package) is not available on this machine.

Fix

Use a font shipped with TeX Live, or add the font files to the project and load them by file name.

Example

Reproduced on TeX Live 2026 by CI · lualatex · corpus/fontspec-font-not-found

Font not installed (fontspec)

Fails: main.tex
\documentclass{article}
\usepackage{fontspec}
\setmainfont{Helvetica Neue Pro}
\begin{document}
Hello.
\end{document}
Fixed
\documentclass{article}
\usepackage{fontspec}
\setmainfont{TeX Gyre Heros}
\begin{document}
Hello.
\end{document}
What TeX prints in main.log
! Package fontspec Error: 
(fontspec)                The font "Helvetica Neue Pro" cannot be found;
(fontspec)                this may be but usually is not a fontspec bug.
(fontspec)                Either there is a typo in the font name/file, the
(fontspec)                font is not installed (correctly), or there is a
(fontspec)                bug in the underlying font loading engine
(fontspec)                (XeTeX/luaotfload).

For immediate help type H <return>.
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l.4 \begin
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