ltpdriver: 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/ltpdriver - from package: ion

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

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