ftppr: 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/ftppr - from package: 3proxy

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

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