emms-print-metadata: 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/emms-print-metadata - from package: emms

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