profnet_isis: 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/profnet_isis - from package: profnet-isis

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