stonevpn: 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/stonevpn - from package: stonevpn

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

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