ed2k_hash: 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/ed2k_hash - from package: ed2k-hash

You may install the required package with command apt-get install {package}
Error in other languages:
ed2k_hash: bevel nie gevind nie
ed2k_hash: comandă negăsită
ed2k_hash: comando não encontrado
ed2k_hash: commande introuvable
ed2k_hash: command not found
ed2k_hash: käsku ei ole
ed2k_hash: không tìm thấy lệnh
ed2k_hash: komanda nerasta
ed2k_hash: Kommando nicht gefunden.
ed2k_hash: kommandot finns inte
ed2k_hash: komut yok
ed2k_hash: nie znaleziono polecenia
ed2k_hash: níor aimsíodh an t-ordú
ed2k_hash: no se encontró la orden
ed2k_hash: no s'ha trobat l'ordre
ed2k_hash: opdracht niet gevonden
ed2k_hash: parancs nem található
ed2k_hash: perintah tidak ditemukan
ed2k_hash: príkaz nenájdený
ed2k_hash: příkaz nenalezen
ed2k_hash: команда не найдена
ed2k_hash: командата не е открита
ed2k_hash: 命令找不到
ed2k_hash: コマンドが見つかりません