guards: 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/guards - from package: quilt

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

On Debian possible default full paths are:

/usr/bin/guards - from package: quilt

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

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