mpdcron: 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/mpdcron - from package: mpdcron

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