loadndisdriver-1.9: command not found

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:

/sbin/loadndisdriver-1.9 - from package: ndiswrapper-utils-1.9

You may install the required package with command apt-get install {package}

Error in other languages:
loadndisdriver-1.9: bevel nie gevind nie
loadndisdriver-1.9: comandă negăsită
loadndisdriver-1.9: comando não encontrado
loadndisdriver-1.9: commande introuvable
loadndisdriver-1.9: command not found
loadndisdriver-1.9: käsku ei ole
loadndisdriver-1.9: không tìm thấy lệnh
loadndisdriver-1.9: komanda nerasta
loadndisdriver-1.9: Kommando nicht gefunden.
loadndisdriver-1.9: kommandot finns inte
loadndisdriver-1.9: komut yok
loadndisdriver-1.9: nie znaleziono polecenia
loadndisdriver-1.9: níor aimsíodh an t-ordú
loadndisdriver-1.9: no se encontró la orden
loadndisdriver-1.9: no s'ha trobat l'ordre
loadndisdriver-1.9: opdracht niet gevonden
loadndisdriver-1.9: parancs nem található
loadndisdriver-1.9: perintah tidak ditemukan
loadndisdriver-1.9: príkaz nenájdený
loadndisdriver-1.9: příkaz nenalezen
loadndisdriver-1.9: команда не найдена
loadndisdriver-1.9: командата не е открита
loadndisdriver-1.9: 命令找不到
loadndisdriver-1.9: コマンドが見つかりません