# Error when compiling: ! Missing = inserted for \ifnum caused by \input Acorn.fd

I've looked for solutions but unfortunately, no solution was applicable to my current case. I do not know where it comes from. This is my sample:

\documentclass[a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage{lettrine}
\usepackage{color}

\definecolor{darkred}{RGB}{80,0,0}

\input Acorn.fd
\newcommand*\initfamily{\usefont{U}{Acorn}{xl}{n}}

\begin{document}
\lettrine[lines=3]{\initfamily\textcolor{darkred}{T}}{he} first paragraph.
\end{document}


I am using TeXnic-Center and MiKTeX. Does anyone know what might cause this error? I'm assuming it's the \input Acorn.fd but my Google search didn't bring up anything related to this error in combination with Acorn.fd.

Edit1: apparently it's being caused by the lettrine package. Any ideas?

Edit2: this is (the relevant) log

(C:\Users\Spooky\AppData\Roaming\MiKTeX\2.9\tex\latex\lettrine\lettrine.sty
File: lettrine.sty 2020-03-14 v2.23 (Daniel Flipo)

Package lettrine Warning: Your LaTeX kernel is too old to provide access
(lettrine)                to former versions of the lettrine package.
(lettrine)                otherwise you are fine; reported on input line 41.

("C:\Program Files\MiKTeX 2.9\tex\latex\graphics\keyval.sty"
Package: keyval 2014/10/28 v1.15 key=value parser (DPC)
\KV@toks@=\toks16
)
(C:\Users\Spooky\AppData\Roaming\MiKTeX\2.9\tex\generic\minifp\minifp.sty
Package: minifp 2013/12/30 v0.96. Macros for real number operations and a stack-based programing language.
\MFP@loopctr=\count87
)
\c@DefaultLines=\count88
\c@DefaultDepth=\count89
\DefaultFindent=\dimen103
\DefaultNindent=\dimen104
\DefaultSlope=\dimen105
\L@lbox=\box26
\L@tbox=\box27
\c@L@lines=\count90
\c@L@depth=\count91
\L@Pindent=\dimen107
\L@Findent=\dimen108
\L@Nindent=\dimen109
\L@lraise=\dimen110
\L@first=\dimen111
\L@next=\dimen112
\L@slope=\dimen113
\L@height=\dimen114
\L@novskip=\dimen115
\L@target@ht=\dimen116
\L@target@dp=\dimen117
\L@target@tht=\dimen118
\LettrineWidth=\dimen119
\LettrineHeight=\dimen120
\LettrineDepth=\dimen121
\Llist@everypar=\toks17

(C:\Users\Spooky\AppData\Roaming\MiKTeX\2.9\tex\latex\lettrine\lettrine.cfg))
! Missing = inserted for \ifnum.
-
l.21

I was expecting to see <', =', or >'. Didn't.


Apparently my LaTeX kernel is too old.

Edit3: this is the start of the .log-file:

This is pdfTeX, Version 3.14159265-2.6-1.40.17 (MiKTeX 2.9.6210 64-bit) (preloaded format=pdflatex 2017.3.24)  26 JUL 2020 07:07
entering extended mode
**./LaTeX.tex
(LaTeX.tex
LaTeX2e <2017/01/01> patch level 1
Babel <3.9r> and hyphenation patterns for 75 language(s) loaded.
("C:\Program Files\MiKTeX 2.9\tex\latex\base\article.cls"

• Can you quote the complete error message from the .log file, please? At the moment my guess is that you get structurally the same error that is described in tex.stackexchange.com/q/422176/35864. lettrine uses the new ISO date format to identify itself (I have lettrine.sty 2020-03-14 v2.23). If you LaTeX kernel is too old, it will throw an error. If you are not close to a tight deadline update your MikTeX installation thoroughly by running the Update at least twice in Admin and User mode (see tex.stackexchange.com/q/108447/35864). – moewe Jul 26 at 7:37
• If you are close to a deadline, you can try adding \RequirePackage[2017/04/15]{latexrelease} as explained in tex.stackexchange.com/q/422176/35864, but this may not work on your system if it is too old. In that case it's probably better to avoid lettrine` for now. – moewe Jul 26 at 7:38
• you should never need to input an fd file, what is the intention here? That said, your document runs without error in texlive2020 – David Carlisle Jul 26 at 9:13
• thank you guys for all your considerations, i added the logs. It's definitely caused by the lettrine package. – Zest Jul 26 at 13:29
• Yup, your LaTeX kernel is too old. Update your MikTeX in Admin and User mode (see my very first comment). – moewe Jul 26 at 14:03