file2udp: 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/file2udp - from package: ion

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

Error in other languages:
file2udp: bevel nie gevind nie
file2udp: comandă negăsită
file2udp: comando não encontrado
file2udp: commande introuvable
file2udp: command not found
file2udp: käsku ei ole
file2udp: không tìm thấy lệnh
file2udp: komanda nerasta
file2udp: Kommando nicht gefunden.
file2udp: kommandot finns inte
file2udp: komut yok
file2udp: nie znaleziono polecenia
file2udp: níor aimsíodh an t-ordú
file2udp: no se encontró la orden
file2udp: no s'ha trobat l'ordre
file2udp: opdracht niet gevonden
file2udp: parancs nem található
file2udp: perintah tidak ditemukan
file2udp: príkaz nenájdený
file2udp: příkaz nenalezen
file2udp: команда не найдена
file2udp: командата не е открита
file2udp: 命令找不到
file2udp: コマンドが見つかりません