gscanbus: 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/gscanbus - from package: gscanbus

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