renrot: command not found

Have You tried accessing the binary with the full path?

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/renrot - from package: renrot

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