stoken-gui: 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 CentOS possible default full paths are:

/usr/bin/stoken-gui - from package: stoken-gui

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/stoken-gui - from package: stoken

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

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