"! Missing endcsname inserted." encountered after MiKTeX version 21.3

[aendie]

• [ ] I have read and acknowledged this HOWTO article:
  Submitting a MiKTeX problem report

I publish code (Nautical Almanacs) that generate LaTeX and it worked flawlessly up MiKTeX version 21.3. Now it crashes with MiKTeX version 21.7 and it appears to be with the \\[0.3cm] at the end of the \includegraphics line. Is this a bug in MiKTeX?

The LaTeX code begins as follows...

\documentclass[10pt, twoside, a4paper]{report}
%\usepackage[utf8]{inputenc}
\usepackage[english]{babel}
\usepackage{fontenc}
\usepackage[nomarginpar, top=10mm, bottom=15mm, left=10mm, right=10mm]{geometry}
\usepackage[table]{xcolor}
% [table] option loads the colortbl package for coloring rows, columns, and cells within tables.
\definecolor{LightCyan}{rgb}{0.88,1,1}
\definecolor{darknight}{rgb}{0.18, 0.27, 0.33}
\usepackage{booktabs}
\definecolor{darknight}{rgb}{0.18, 0.27, 0.33}
\definecolor{khaki}{rgb}{0.76, 0.69, 0.57}
\usepackage{multirow}
\newcommand{\HRule}{\rule{\linewidth}{0.5mm}}
\setlength{\footskip}{15pt}
\usepackage[pdftex]{graphicx}   % for \includegraphics
\usepackage{tikz}               % for \draw  (load after 'graphicx')
%\showboxbreadth=50  % use for logging
%\showboxdepth=50    % use for logging
%\DeclareUnicodeCharacter{00B0}{\ensuremath{{}^\circ}}
\setlength\fboxsep{1.5pt}       % ONLY used by \colorbox in alma_skyfield.py
\begin{document}
% for the title page only...
\newgeometry{nomarginpar, top=21mm, bottom=15mm, left=10mm, right=10mm}
    \begin{titlepage}
    \begin{center}
    \textsc{\Large Generated using Ephem and Skyfield}\\
    \large http://rhodesmill.org/skyfield/\\[0.7cm]
    % TRIM values: left bottom right top
    \includegraphics[clip, trim=12mm 20cm 12mm 21mm, width=0.92\textwidth]{C:\\Python39\\Lib\\site-packages\\skyalmanac\\data\\A4chart0-180_P.pdf}\\[0.3cm]
    \includegraphics[clip, trim=12mm 20cm 12mm 21mm, width=0.92\textwidth]{C:\\Python39\\Lib\\site-packages\\skyalmanac\\data\\A4chart180-360_P.pdf}\\[1.5cm]
    \textsc{\huge The Nautical Almanac}\\[1.0cm]
    \HRule \\[0.5cm]
    { \Huge \bfseries 2021}\\[0.2cm]
    \HRule \\
    \begin{center}\begin{tabular}[t]{rl}
    \large\emph{Author:} & \large Andrew \textsc{Bauer}\\
    \large\emph{Original concept from:} & \large Enno \textsc{Rodegerdts}\\
    \end{tabular}\end{center}
    {\large \today}
    \HRule \\[0.2cm]
    \end{center}
    \begin{description}\footnotesize
    \item[Disclaimer:] These are computer generated tables - use them at your own risk.
    The accuracy has been randomly checked with JPL HORIZONS System, but cannot be guaranteed.
    This means I cannot be held liable if you get lost on the oceans because of errors in this publication.
    Besides, this publication only contains the 'daily pages' of the Nautical Almanac: an official version of the Nautical Almanac is indispensable.
    \end{description}
\end{titlepage}

and pdflatex filename.tex fails as follows:

This is pdfTeX, Version 3.141592653-2.6-1.40.23 (MiKTeX 21.7)
entering extended mode
(almanac_2021.tex
LaTeX2e <2021-06-01> patch level 1
L3 programming layer <2021-07-12>
(C:\Program Files\MiKTeX\tex/latex/base\report.cls
Document Class: report 2021/02/12 v1.4n Standard LaTeX document class
(C:\Program Files\MiKTeX\tex/latex/base\size10.clo))
(C:\Program Files\MiKTeX\tex/generic/babel\babel.sty
(C:\Program Files\MiKTeX\tex/generic/babel\babel.def
(C:\Program Files\MiKTeX\tex/generic/babel\txtbabel.def))
*************************************
* Local config file bblopts.cfg used
*
(C:\Program Files\MiKTeX\tex/latex/arabi\bblopts.cfg)
(C:\Program Files\MiKTeX\tex/latex/babel-english\english.ldf))
(C:\Program Files\MiKTeX\tex/latex/base\fontenc.sty)
(C:\Program Files\MiKTeX\tex/latex/geometry\geometry.sty
(C:\Program Files\MiKTeX\tex/latex/graphics\keyval.sty)
(C:\Program Files\MiKTeX\tex/generic/iftex\ifvtex.sty
(C:\Program Files\MiKTeX\tex/generic/iftex\iftex.sty))
(C:\Program Files\MiKTeX\tex/latex/geometry\geometry.cfg))
(C:\Program Files\MiKTeX\tex/latex/xcolor\xcolor.sty
(C:\Program Files\MiKTeX\tex/latex/graphics-cfg\color.cfg)
(C:\Program Files\MiKTeX\tex/latex/graphics-def\pdftex.def)
(C:\Program Files\MiKTeX\tex/latex/colortbl\colortbl.sty
(C:\Program Files\MiKTeX\tex/latex/tools\array.sty)))
(C:\Program Files\MiKTeX\tex/latex/booktabs\booktabs.sty)
(C:\Program Files\MiKTeX\tex/latex/multirow\multirow.sty)
(C:\Program Files\MiKTeX\tex/latex/graphics\graphicx.sty
(C:\Program Files\MiKTeX\tex/latex/graphics\graphics.sty
(C:\Program Files\MiKTeX\tex/latex/graphics\trig.sty)
(C:\Program Files\MiKTeX\tex/latex/graphics-cfg\graphics.cfg)))
(C:\Program Files\MiKTeX\tex/latex/pgf/frontendlayer\tikz.sty
(C:\Program Files\MiKTeX\tex/latex/pgf/basiclayer\pgf.sty
(C:\Program Files\MiKTeX\tex/latex/pgf/utilities\pgfrcs.sty
(C:\Program Files\MiKTeX\tex/generic/pgf/utilities\pgfutil-common.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/utilities\pgfutil-common-lists.tex))
(C:\Program Files\MiKTeX\tex/generic/pgf/utilities\pgfutil-latex.def)
(C:\Program Files\MiKTeX\tex/generic/pgf/utilities\pgfrcs.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf\pgf.revision.tex)))
(C:\Program Files\MiKTeX\tex/latex/pgf/basiclayer\pgfcore.sty
(C:\Program Files\MiKTeX\tex/latex/pgf/systemlayer\pgfsys.sty
(C:\Program Files\MiKTeX\tex/generic/pgf/systemlayer\pgfsys.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/utilities\pgfkeys.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/utilities\pgfkeysfiltered.code.tex))
(C:\Program Files\MiKTeX\tex/generic/pgf/systemlayer\pgf.cfg)
(C:\Program Files\MiKTeX\tex/generic/pgf/systemlayer\pgfsys-pdftex.def
(C:\Program Files\MiKTeX\tex/generic/pgf/systemlayer\pgfsys-common-pdf.def)))
(C:\Program Files\MiKTeX\tex/generic/pgf/systemlayer\pgfsyssoftpath.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/systemlayer\pgfsysprotocol.code.tex))
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcore.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmath.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathcalc.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathutil.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathparser.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.basic.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.trigonometric.co
de.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.random.code.tex)

(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.comparison.code.
tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.base.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.round.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.misc.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfunctions.integerarithmeti
cs.code.tex)))
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmathfloat.code.tex))
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfint.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorepoints.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorepathconstruct.code.t
ex)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorepathusage.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorescopes.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcoregraphicstate.code.te
x)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcoretransformations.code
.tex) (C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorequick.code.tex
) (C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcoreobjects.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorepathprocessing.code.
tex) (C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorearrows.code.tex
) (C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcoreshade.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcoreimage.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcoreexternal.code.tex))
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorelayers.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcoretransparency.code.te
x) (C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorepatterns.code.tex
) (C:\Program Files\MiKTeX\tex/generic/pgf/basiclayer\pgfcorerdf.code.tex)))
(C:\Program Files\MiKTeX\tex/generic/pgf/modules\pgfmoduleshapes.code.tex)
(C:\Program Files\MiKTeX\tex/generic/pgf/modules\pgfmoduleplot.code.tex)
(C:\Program Files\MiKTeX\tex/latex/pgf/compatibility\pgfcomp-version-0-65.sty)
(C:\Program Files\MiKTeX\tex/latex/pgf/compatibility\pgfcomp-version-1-18.sty))
 (C:\Program Files\MiKTeX\tex/latex/pgf/utilities\pgffor.sty
(C:\Program Files\MiKTeX\tex/latex/pgf/utilities\pgfkeys.sty
(C:\Program Files\MiKTeX\tex/generic/pgf/utilities\pgfkeys.code.tex))
(C:\Program Files\MiKTeX\tex/latex/pgf/math\pgfmath.sty
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmath.code.tex))
(C:\Program Files\MiKTeX\tex/generic/pgf/utilities\pgffor.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/math\pgfmath.code.tex)))
(C:\Program Files\MiKTeX\tex/generic/pgf/frontendlayer/tikz\tikz.code.tex
(C:\Program Files\MiKTeX\tex/generic/pgf/libraries\pgflibraryplothandlers.code.
tex) (C:\Program Files\MiKTeX\tex/generic/pgf/modules\pgfmodulematrix.code.tex)

(C:\Program Files\MiKTeX\tex/generic/pgf/frontendlayer/tikz/libraries\tikzlibra
rytopaths.code.tex)))
(C:\Program Files\MiKTeX\tex/latex/l3backend\l3backend-pdftex.def)
No file almanac_2021.aux.
*geometry* driver: auto-detecting
*geometry* detected driver: pdftex
(C:\Program Files\MiKTeX\tex/context/base/mkii\supp-pdf.mkii
[Loading MPS to PDF converter (version 2006.09.02).]
) (C:\Program Files\MiKTeX\tex/latex/epstopdf-pkg\epstopdf-base.sty
(C:\Program Files\MiKTeX\tex/latex/00miktex\epstopdf-sys.cfg))
! Missing endcsname inserted.
<to be read again>
                   unskip
l.30 ...ges\\skyalmanac\\data\\A4chart0-180_P.pdf}
                                                  \\[0.3cm]
?

Any suggestions on how I can fix my code (or is this a new MiKTeX issue)?

Kind Regards ... all assistance greatly appreciated.

[edocevoli]

This is not a MiKTeX-specific issue.

[aendie]

Okay... it worked in MiKTeX 21.3 and it fails in MiKTeX 21.7, so somewhere in between the problem occurred. I have no idea where to look next. Is this an issue that you can ignore without even a message to the offending party? I would really appreciate your expert advice and your comment on "can double backslash with a vertical spacing argument just fail and be ignored?". Is it a problem with \includegraphics ? MiKTeX has worked wonderfully for the past 7 years or so.

[edocevoli]

Sorry, but I am not a LaTeX expert. This issue tracker is not a support/help forum.