ftpwatch: 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/ftpwatch - from package: ftpwatch

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

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