owx-check: 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/owx-check - from package: owx

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

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