gupnp-upload: command not found

Have You tried accessing the binary with the full path?

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/gupnp-upload - from package: gupnp-tools

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