Impossible to use TL 2023 on Windows

[Denis Bitouzé]

Hi,

a student of mine used to have a working TL 2021 on Windows (10). He
just removed it (using Add/Remove Programs) and installed TL 2023 (as
administrator).

But, since then, it is impossible to run LaTeX. For instance, in the
terminal (`cmd.exe`), `pdflatex test` tries to regenerate the pdflatex
format (`pdflatex.fmt`) but fails with the error:

  ┌────
  │ Can't spawn "cmd.exe": No such file or directory at
  │ c:\texlive\...\fmtutil.pl line 727.
  └────

Any help would be greatly appreciated: my student is desperate!

Thanks!
-- 
Denis