td-util: 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/sbin/td-util - from package: blktap-utils

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