icclu: 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
/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/icclu - from package: argyll

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