icmun: 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/icmun - from package: icmake

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

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