quot: 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/sbin/quot - from package: quota

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

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