minidlnad: 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/minidlnad - from package: minidlna

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