rlprd: 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/rlprd - from package: rlpr

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

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