SNHELLO: 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/sbin/SNHELLO - from package: sn

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

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