bld-pf_policy: 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/bld-pf_policy - from package: bld-postfix

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