pmt-ehd: 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/sbin/pmt-ehd - from package: libpam-mount

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

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