courierlogger: 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/courierlogger - from package: courier-authlib

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