rpc.rquotad: 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/sbin/rpc.rquotad - from package: quota

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

On Debian possible default full paths are:

/usr/sbin/rpc.rquotad - from package: quota

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

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