directoryassistant: 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/bin/directoryassistant - from package: directoryassistant

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