mid3v2: 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 CentOS possible default full paths are:

/usr/bin/mid3v2 - from package: python-mutagen

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/mid3v2 - from package: python-mutagen

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

Error in other languages:
mid3v2: bevel nie gevind nie
mid3v2: comandă negăsită
mid3v2: comando não encontrado
mid3v2: commande introuvable
mid3v2: command not found
mid3v2: käsku ei ole
mid3v2: không tìm thấy lệnh
mid3v2: komanda nerasta
mid3v2: Kommando nicht gefunden.
mid3v2: kommandot finns inte
mid3v2: komut yok
mid3v2: nie znaleziono polecenia
mid3v2: níor aimsíodh an t-ordú
mid3v2: no se encontró la orden
mid3v2: no s'ha trobat l'ordre
mid3v2: opdracht niet gevonden
mid3v2: parancs nem található
mid3v2: perintah tidak ditemukan
mid3v2: príkaz nenájdený
mid3v2: příkaz nenalezen
mid3v2: команда не найдена
mid3v2: командата не е открита
mid3v2: 命令找不到
mid3v2: コマンドが見つかりません