sparkclean: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH

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/sparkclean - from package: spark

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