in.nnrpd: 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:

/usr/sbin/in.nnrpd - from package: inn

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

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