latexpand: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/latexpand - from package: texlive-extra-utils

You may install the required package with command apt-get install {package}
Error in other languages:
latexpand: bevel nie gevind nie
latexpand: comandă negăsită
latexpand: comando não encontrado
latexpand: commande introuvable
latexpand: command not found
latexpand: käsku ei ole
latexpand: không tìm thấy lệnh
latexpand: komanda nerasta
latexpand: Kommando nicht gefunden.
latexpand: kommandot finns inte
latexpand: komut yok
latexpand: nie znaleziono polecenia
latexpand: níor aimsíodh an t-ordú
latexpand: no se encontró la orden
latexpand: no s'ha trobat l'ordre
latexpand: opdracht niet gevonden
latexpand: parancs nem található
latexpand: perintah tidak ditemukan
latexpand: príkaz nenájdený
latexpand: příkaz nenalezen
latexpand: команда не найдена
latexpand: командата не е открита
latexpand: 命令找不到
latexpand: コマンドが見つかりません