nasty: 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/nasty - from package: nasty

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

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