cortina: 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/cortina - from package: cortina

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