mkcue: 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/mkcue - from package: mkcue

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

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