midicopy: command not found

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/midicopy - from package: abcmidi

You may install the required package with command apt-get install {package}

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