intltool-update: 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 CentOS possible default full paths are:

/usr/bin/intltool-update - from package: intltool

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/intltool-update - from package: intltool

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

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