我格式化了我的 PC，然后安装了 MikTeX 和 TexStudio。现在我无法编译我的代码。出现的错误是：
Package ifluatex Error: Name clash, \ifluatex is already defined }
在格式化 PC 之前，一切都在编译，我不知道还能做什么。我清除了代码，但仍然出现相同的错误。
\documentclass[12pt,a4paper, oneside, hidelinks]{abntex2}
\usepackage [utf8] {inputenc}
\usepackage{lipsum}
\usepackage{graphicx}
\usepackage{leading}
\usepackage{indentfirst}
\usepackage{enumerate}
\usepackage{setspace}
\usepackage[footnotesize]{caption}
\usepackage{amsmath, amsthm, amssymb, amsfonts, amstext}
\usepackage{color}
\usepackage{listings}
\usepackage[dvipsnames,table,xcdraw]{xcolor}
\usepackage[bottom=2cm,top=3cm,left=3cm,right=2cm, headheight=17pt ]{geometry}
\renewcommand{\rmdefault}{phv}
\renewcommand{\sfdefault}{phv}
\usepackage{lastpage}
\usepackage{multirow}
\usepackage[alf]{abntex2cite}
\usepackage{tikz}
\usepackage{titlesec }
\usepackage{fancyhdr}
\autor{xx }
\titulo{xx}
\local{xx}
\data{xx}
\preambulo{xxx}
\tipotrabalho{xx}
\begin{document}
Hello
\end{document}
该错误定义在文件日志文件的第 174 行，如下图所示：
“日志文件 ifluatex.sty”的完整文件如下。
%%
%% This is file `ifluatex.sty',
%% generated with the docstrip utility.
%%
%% The original source files were:
%%
%% ifluatex.dtx (with options: `package')
%%
%% This is a generated file.
%%
%% Project: ifluatex
%% Version: 2016/05/16 v1.4
%%
%% Copyright (C) 2007, 2009, 2010 by
%% Heiko Oberdiek <heiko.oberdiek at googlemail.com>
%%
%% This work may be distributed and/or modified under the
%% conditions of the LaTeX Project Public License, either
%% version 1.3c of this license or (at your option) any later
%% version. This version of this license is in
%% http://www.latex-project.org/lppl/lppl-1-3c.txt
%% and the latest version of this license is in
%% http://www.latex-project.org/lppl.txt
%% and version 1.3 or later is part of all distributions of
%% LaTeX version 2005/12/01 or later.
%%
%% This work has the LPPL maintenance status "maintained".
%%
%% This Current Maintainer of this work is Heiko Oberdiek.
%%
%% The Base Interpreter refers to any `TeX-Format',
%% because some files are installed in TDS:tex/generic//.
%%
%% This work consists of the main source file ifluatex.dtx
%% and the derived files
%% ifluatex.sty, ifluatex.pdf, ifluatex.ins, ifluatex.drv,
%% ifluatex-test1.tex, ifluatex-test2.tex, ifluatex-test3.tex.
%%
\begingroup\catcode61\catcode48\catcode32=10\relax%
\catcode13=5 % ^^M
\endlinechar=13 %
\catcode35=6 % #
\catcode39=12 % '
\catcode44=12 % ,
\catcode45=12 % -
\catcode46=12 % .
\catcode58=12 % :
\catcode64=11 % @
\catcode123=1 % {
\catcode125=2 % }
\expandafter\let\expandafter\x\csname [email protected]\endcsname
\ifx\x\relax % plain-TeX, first loading
\else
\def\empty{}%
\ifx\x\empty % LaTeX, first loading,
% variable is initialized, but \ProvidesPackage not yet seen
\else
\expandafter\ifx\csname PackageInfo\endcsname\relax
\def\x#1#2{%
\immediate\write-1{Package #1 Info: #2.}%
}%
\else
\def\x#1#2{\PackageInfo{#1}{#2, stopped}}%
\fi
\x{ifluatex}{The package is already loaded}%
\aftergroup\endinput
\fi
\fi
\endgroup%
\begingroup\catcode61\catcode48\catcode32=10\relax%
\catcode13=5 % ^^M
\endlinechar=13 %
\catcode35=6 % #
\catcode39=12 % '
\catcode40=12 % (
\catcode41=12 % )
\catcode44=12 % ,
\catcode45=12 % -
\catcode46=12 % .
\catcode47=12 % /
\catcode58=12 % :
\catcode64=11 % @
\catcode91=12 % [
\catcode93=12 % ]
\catcode123=1 % {
\catcode125=2 % }
\expandafter\ifx\csname ProvidesPackage\endcsname\relax
\def\x#1#2#3[#4]{\endgroup
\immediate\write-1{Package: #3 #4}%
\xdef#1{#4}%
}%
\else
\def\x#1#2[#3]{\endgroup
#2[{#3}]%
\ifx#1\@undefined
\xdef#1{#3}%
\fi
\ifx#1\relax
\xdef#1{#3}%
\fi
}%
\fi
\expandafter\x\csname [email protected]\endcsname
\ProvidesPackage{ifluatex}%
[2016/05/16 v1.4 Provides the ifluatex switch (HO)]%
\begingroup\catcode61\catcode48\catcode32=10\relax%
\catcode13=5 % ^^M
\endlinechar=13 %
\catcode123=1 % {
\catcode125=2 % }
\catcode64=11 % @
\def\x{\endgroup
\expandafter\edef\csname ifluatex@AtEnd\endcsname{%
\endlinechar=\the\endlinechar\relax
\catcode13=\the\catcode13\relax
\catcode32=\the\catcode32\relax
\catcode35=\the\catcode35\relax
\catcode61=\the\catcode61\relax
\catcode64=\the\catcode64\relax
\catcode123=\the\catcode123\relax
\catcode125=\the\catcode125\relax
}%
}%
\x\catcode61\catcode48\catcode32=10\relax%
\catcode13=5 % ^^M
\endlinechar=13 %
\catcode35=6 % #
\catcode64=11 % @
\catcode123=1 % {
\catcode125=2 % }
\def\TMP@EnsureCode#1#2{%
\edef\ifluatex@AtEnd{%
\ifluatex@AtEnd
\catcode#1=\the\catcode#1\relax
}%
\catcode#1=#2\relax
}
\TMP@EnsureCode{10}{12}% ^^J
\TMP@EnsureCode{39}{12}% '
\TMP@EnsureCode{40}{12}% (
\TMP@EnsureCode{41}{12}% )
\TMP@EnsureCode{44}{12}% ,
\TMP@EnsureCode{45}{12}% -
\TMP@EnsureCode{46}{12}% .
\TMP@EnsureCode{47}{12}% /
\TMP@EnsureCode{58}{12}% :
\TMP@EnsureCode{60}{12}% <
\TMP@EnsureCode{94}{7}% ^
\TMP@EnsureCode{96}{12}% `
\edef\ifluatex@AtEnd{\ifluatex@AtEnd\noexpand\endinput}
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname PackageError\endcsname\relax
\def\ifluatex@Error#1#2{%
\begingroup
\newlinechar=10 %
\def\MessageBreak{^^J}%
\edef\x{\errhelp{#2}}%
\x
\errmessage{Package ifluatex Error: #1}%
\endgroup
}%
\else
\def\ifluatex@Error{%
\PackageError{ifluatex}%
}%
\fi
\begingroup
\expandafter\ifx\csname ifluatex\endcsname\relax
\else
\edef\i/{\expandafter\string\csname ifluatex\endcsname}%
\ifluatex@Error{Name clash, \i/ is already defined}{%
Incompatible versions of \i/ can cause problems,\MessageBreak
therefore package loading is aborted.%
}%
\endgroup
\expandafter\ifluatex@AtEnd
\fi%
\endgroup
\let\ifluatex\iffalse
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname luatexversion\endcsname\relax
\else
\expandafter\let\csname ifluatex\expandafter\endcsname
\csname iftrue\endcsname
\fi
\ifluatex
\else
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname directlua\endcsname\relax
\else
\expandafter\let\csname ifluatex\expandafter\endcsname
\csname iftrue\endcsname
\begingroup
\newlinechar=10 %
\endlinechar=\newlinechar%
\ifnum0%
\directlua{%
if tex.enableprimitives then
tex.enableprimitives('ifluatex', {'luatexversion'})
tex.print('1')
end
}%
\ifx\ifluatexluatexversion\@undefined\else 1\fi %
=11 %
\global\let\luatexversion\ifluatexluatexversion%
\else%
\ifluatex@Error{%
Missing \string\luatexversion%
}{%
Update LuaTeX.%
}%
\fi%
\endgroup%
\fi
\fi
\ifluatex
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname luatexrevision\endcsname\relax
\ifnum\luatexversion<36 %
\else
\begingroup
\ifx\luatexrevision\relax
\let\luatexrevision\@undefined
\fi
\newlinechar=10 %
\endlinechar=\newlinechar%
\ifcase0%
\directlua{%
if tex.enableprimitives then
tex.enableprimitives('ifluatex', {'luatexrevision'})
else
tex.print('1')
end
}%
\ifx\ifluatexluatexrevision\@undefined 1\fi%
\relax%
\global\let\luatexrevision\ifluatexluatexrevision%
\fi%
\endgroup%
\fi
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname luatexrevision\endcsname\relax
\ifluatex@Error{%
Missing \string\luatexrevision%
}{%
Update LuaTeX.%
}%
\fi
\fi
\fi
\begingroup
\expandafter\ifx\csname PackageInfo\endcsname\relax
\def\x#1#2{%
\immediate\write-1{Package #1 Info: #2.}%
}%
\else
\let\x\PackageInfo
\expandafter\let\csname on@line\endcsname\empty
\fi
\x{ifluatex}{LuaTeX \ifluatex\else not \fi detected}%
\endgroup
\ifluatex@AtEnd%
\endinput
%%
%% End of file `ifluatex.sty'.
答案1
找到解决方案了 !!!! 按照 @daleif 的建议，我在管理员和用户模式下更新了“MikTex 控制台”，问题就解决了。
非常感谢@daleif。
下面是显示管理员模式下控制台更新的图片，供大家查看。
答案2
确实，解决方案是更新。我今天开始遇到与您描述的相同问题，从图片中可以看出，一切都来自 2018 年：
更新后，问题得到解决。