Arabic characters does not appear, arabi package

Question

I am trying to write some Arabic using arabi package. Here is the code:

\documentclass{article}

\usepackage[utf8]{inputenc}
\usepackage[LAE]{fontenc}
\usepackage[arabic]{babel}


\begin{document}
\selectlanguage{arabic}
مرحبا
\end{document}

I get a blank page with only Arabic number one at the bottom of the page.

My operating system is macOS Sierra, and I use xelatex from MikTex.

Output:

This is XeTeX, Version 3.14159265-2.6-0.99998 (MiKTeX 2.9.6500)
entering extended mode
(ara.tex
LaTeX2e <2017-04-15>
Babel <3.17> and hyphenation patterns for 1 language(s) loaded.
(/usr/local/share/miktex-texmf/tex/latex/base/article.cls
Document Class: article 2014/09/29 v1.4h Standard LaTeX document class
(/usr/local/share/miktex-texmf/tex/latex/base/size10.clo))
(/usr/local/share/miktex-texmf/tex/latex/base/inputenc.sty

Package inputenc Warning: inputenc package ignored with utf8 based engines.

) (/usr/local/share/miktex-texmf/tex/latex/base/fontenc.sty
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/laeenc.def)
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/laecmr.fd))
(/usr/local/share/miktex-texmf/tex/generic/babel/babel.sty
(/usr/local/share/miktex-texmf/tex/generic/babel/switch.def)
*************************************
* Local config file bblopts.cfg used
*
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/bblopts.cfg)
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/arabic.ldf
(/usr/local/share/miktex-texmf/tex/generic/babel/babel.def
(/usr/local/share/miktex-texmf/tex/generic/babel/switch.def)
(/usr/local/share/miktex-texmf/tex/generic/babel/xebabel.def
(/usr/local/share/miktex-texmf/tex/generic/babel/txtbabel.def)))

Package babel Warning: No hyphenation patterns were preloaded for
(babel)                the language `Arabic' into the format.
(babel)                Please, configure your TeX system to add them and
(babel)                rebuild the format. Now I will use the patterns
(babel)                preloaded for \language=0 instead on input line 35.

Loading the definitions for the LaTeX{} Arabic encoding
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/laeenc.def)
Loading the Common definitions for Arabic and Farsi
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/arabicore.sty
  Arabi Core switching commands v1.0  2006/01/01   (may still change)  )
Loading the Arabi fonts definitions for Arabic
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/arabicfnt.sty
  Arabic font switching commands v1.0  2006/01/01   (may still change)  )
Loading the Common definitions for Arabic and Farsi
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/arabnovowel.sty)
*************************************
* Local config file arabic.cfg used
*
(/Users/taha/.miktex/texmfs/install/tex/latex/arabi/arabic.cfg))) (ara.aux

LaTeX Font Warning: Font shape `LAE/lmr/m/n' undefined
(Font)              using `LAE/cmr/m/n' instead on input line 3.

) (/usr/local/share/miktex-texmf/tex/latex/base/ifthen.sty)
(/usr/local/share/miktex-texmf/tex/latex/lm/ot1lmr.fd) [1] (ara.aux)

LaTeX Font Warning: Some font shapes were not available, defaults substituted.

 )
(see the transcript file for additional information)
Output written on ara.pdf (1 page).
Transcript written on ara.log.

Answer 1

Since you are compiling with XeTeX, don't load fontenc or inputenc. You want to use fontspec. Rather than babel, you probably want polyglossia.

Here's a very simple example. You need to specify a suitable font available on your system. On my system, Noto Naskh Arabic supports Arabic.

\documentclass{article}
\usepackage{polyglossia}
\setmainlanguage{arabic}
\newfontfamily\arabicfont[Script=Arabic]{Noto Naskh Arabic}
\begin{document}
مرحبا
\end{document}