metarefresh.php: 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/share/simplesamlphp/modules/metarefresh/bin/metarefresh.php - from package: simplesamlphp

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

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