I can't find the format file xelatex.fmt

try to run sudo fmtutil-sys --all which should create all missing format files.

If you installed TeX from the repositories of your Linux system, you could reinstall the xetex package from a repository.

• Redhat/Fedora: sudo yum reinstall texlive-xetex

• Debian/Ubuntu: sudo apt-get install --reinstall texlive-xetex

Make sure that you have the proper LaTeX packages installed in addition to the XeLaTeX ones.

In my installation of TeX Live on a Mac, I initially didn't have the latex or latex-bin packages installed, but I did have xetex installed. Running xelatex would result in the error message given by cyberscientist.

Try the following to install the LaTeX packages and generate xelatex.fmt:

tlmgr install latex latex-bin
fmtutil ---all

If you need to do things systemwide rather than in your user directory, try

sudo tlmgr install latex latex-bin
sudo tlmgr-sys --all

For me this unintuitively resulted in generation of xelatex.fmt. xelatex now runs successfully.