i1620: 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/i1620 - from package: simh

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

Error in other languages:
i1620: bevel nie gevind nie
i1620: comandă negăsită
i1620: comando não encontrado
i1620: commande introuvable
i1620: command not found
i1620: käsku ei ole
i1620: không tìm thấy lệnh
i1620: komanda nerasta
i1620: Kommando nicht gefunden.
i1620: kommandot finns inte
i1620: komut yok
i1620: nie znaleziono polecenia
i1620: níor aimsíodh an t-ordú
i1620: no se encontró la orden
i1620: no s'ha trobat l'ordre
i1620: opdracht niet gevonden
i1620: parancs nem található
i1620: perintah tidak ditemukan
i1620: príkaz nenájdený
i1620: příkaz nenalezen
i1620: команда не найдена
i1620: командата не е открита
i1620: 命令找不到
i1620: コマンドが見つかりません