DigestorMotif: 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/DigestorMotif - from package: topp

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