nuttcp: 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/nuttcp - from package: nuttcp

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

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