smtube: 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

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/smtube - from package: smtube

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