xstarfish: 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/xstarfish - from package: xstarfish

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

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