Enumerate returns an error

Question

Enumitem returning an error. Same with [shortlabels] and [inline] options.

\documentclass{article}
    \usepackage{enumitem}
    \begin{document}
    \begin{enumerate}[label={\textbf{\alph*})}]
        \item Heisenberg
        \item Ozark
        \item Lucifer
    \end{enumerate}
\end{document}

Even without any label, if enumitem is imported, it's showing an error.

Error: Undefined control sequence. \begin{enumerate}[label={\textbf{\alph*})}]

Is it an issue of package dependency?

Log File:

This is pdfTeX, Version 3.14159265-2.6-1.40.21 (MiKTeX 20.6.29) (preloaded format=pdflatex 2020.7.11)  11 JUL 2020 15:10
entering extended mode
**./texstudio_yCzdWs.tex
(texstudio_yCzdWs.tex
LaTeX2e <2020-02-02> patch level 5
L3 programming layer <2020-06-18>
(D:\Labs\LaTeX\MiKTeX\tex/latex/base\article.cls
Document Class: article 2019/12/20 v1.4l Standard LaTeX document class
(D:\Labs\LaTeX\MiKTeX\tex/latex/base\size10.clo
File: size10.clo 2019/12/20 v1.4l Standard LaTeX file (size option)
)
\c@part=\count167
\c@section=\count168
\c@subsection=\count169
\c@subsubsection=\count170
\c@paragraph=\count171
\c@subparagraph=\count172
\c@figure=\count173
\c@table=\count174
\abovecaptionskip=\skip47
\belowcaptionskip=\skip48
\bibindent=\dimen134
)
(D:\Labs\LaTeX\MiKTeX\tex/latex/enumitem\enumitem.sty
Package: enumitem 2019/06/20 v3.9 Customized lists
\enitkv@toks@=\toks15
\enit@outerparindent=\dimen135
\enit@toks=\toks16
\enit@inbox=\box45
\enit@count@id=\count175
\enitdp@description=\count176
)
(D:\Labs\LaTeX\MiKTeX\tex/latex/l3backend\l3backend-pdfmode.def
File: l3backend-pdfmode.def 2020-06-29 L3 backend support: PDF mode
\l__kernel_color_stack_int=\count177
\l__pdf_internal_box=\box46
)
(texstudio_yCzdWs.aux)
\openout1 = `texstudio_yCzdWs.aux'.

LaTeX Font Info:    Checking defaults for OML/cmm/m/it on input line 3.
LaTeX Font Info:    ... okay on input line 3.
LaTeX Font Info:    Checking defaults for OMS/cmsy/m/n on input line 3.
LaTeX Font Info:    ... okay on input line 3.
LaTeX Font Info:    Checking defaults for OT1/cmr/m/n on input line 3.
LaTeX Font Info:    ... okay on input line 3.
LaTeX Font Info:    Checking defaults for T1/cmr/m/n on input line 3.
LaTeX Font Info:    ... okay on input line 3.
LaTeX Font Info:    Checking defaults for TS1/cmr/m/n on input line 3.
LaTeX Font Info:    ... okay on input line 3.
LaTeX Font Info:    Checking defaults for OMX/cmex/m/n on input line 3.
LaTeX Font Info:    ... okay on input line 3.
LaTeX Font Info:    Checking defaults for U/cmr/m/n on input line 3.
LaTeX Font Info:    ... okay on input line 3.

! Undefined control sequence.
\enit@preset ...let \enit@ref \relax \labelindent 
                                                  \z@skip \ifnum \@listdepth...
l.4 \begin{enumerate}[label={\textbf{\alph*})}]
                                               
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.

! Missing number, treated as zero.
<to be read again> 
                   \enit@shl 
l.4 \begin{enumerate}[label={\textbf{\alph*})}]
                                               
A number should have been here; I inserted `0'.
(If you can't figure out why I needed to see a number,
look up `weird error' in the index to The TeXbook.)

! Undefined control sequence.
\enit@calcleft ... \advance \dimen@ -\labelindent 
                                                  \ifcase \enit@calc \enit@c...
l.4 \begin{enumerate}[label={\textbf{\alph*})}]
                                               
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.

! Missing number, treated as zero.
<to be read again> 
                   \advance 
l.4 \begin{enumerate}[label={\textbf{\alph*})}]
                                               
A number should have been here; I inserted `0'.
(If you can't figure out why I needed to see a number,
look up `weird error' in the index to The TeXbook.)

! Illegal unit of measure (pt inserted).
<to be read again> 
                   \advance 
l.4 \begin{enumerate}[label={\textbf{\alph*})}]
                                               
Dimensions can be in units of em, ex, in, pt, pc,
cm, mm, dd, cc, nd, nc, bp, or sp; but yours is a new one!
I'll assume that you meant to say pt, for printer's points.
To recover gracefully from this error, it's best to
delete the erroneous units; e.g., type `2' to delete
two letters. (See Chapter 27 of The TeXbook.)

! Undefined control sequence.
\enit@calcleft ...calcwidth \advance \labelindent 
                                                  \dimen@ \or \labelwidth \d...
l.4 \begin{enumerate}[label={\textbf{\alph*})}]
                                               
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.

! Missing number, treated as zero.
<to be read again> 
                   \relax 
l.4 \begin{enumerate}[label={\textbf{\alph*})}]
                                               
A number should have been here; I inserted `0'.
(If you can't figure out why I needed to see a number,
look up `weird error' in the index to The TeXbook.)

! Illegal unit of measure (pt inserted).
<to be read again> 
                   \relax 
l.4 \begin{enumerate}[label={\textbf{\alph*})}]
                                               
Dimensions can be in units of em, ex, in, pt, pc,
cm, mm, dd, cc, nd, nc, bp, or sp; but yours is a new one!
I'll assume that you meant to say pt, for printer's points.
To recover gracefully from this error, it's best to
delete the erroneous units; e.g., type `2' to delete
two letters. (See Chapter 27 of The TeXbook.)

[1

{C:/Users/AppData/Local/MiKTeX/2.9/pdftex/config/pdftex.map}]
(texstudio_yCzdWs.aux) ) 
Here is how much of TeX's memory you used:
 688 strings out of 480790
 11697 string characters out of 2908470
 244485 words of memory out of 3000000
 16776 multiletter control sequences out of 15000+200000
 532646 words of font info for 25 fonts, out of 3000000 for 9000
 1141 hyphenation exceptions out of 8191
 25i,4n,19p,158b,183s stack positions out of 5000i,500n,10000p,200000b,50000s
<D:/Labs/LaTeX/MiKTeX/fonts/type1/public/amsfonts/cm/cm
bx10.pfb><D:/Labs/LaTeX/MiKTeX/fonts/type1/public/amsfonts/cm/cmr10.pfb>
Output written on texstudio_yCzdWs.pdf (1 page, 23384 bytes).
PDF statistics:
 14 PDF objects out of 1000 (max. 8388607)
 0 named destinations out of 1000 (max. 500000)
 1 words of extra memory for PDF output out of 10000 (max. 10000000)

Answer 1

I fixed it. I had to reinstall the package. Turns out the \newlength\labelindent at line 139 got commented.