uux: 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/uux - from package: uucp

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

On Debian possible default full paths are:

/usr/bin/uux - from package: uucp

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

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