ctanglex: command not found

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/ctanglex - from package: cwebx

You may install the required package with command apt-get install {package}

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