seyon-emu: 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/seyon-emu - from package: seyon

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

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