codebehind1.dll: 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/share/asp.net-demos/bin/codebehind1.dll - from package: asp.net-examples

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

Error in other languages:
codebehind1.dll: bevel nie gevind nie
codebehind1.dll: comandă negăsită
codebehind1.dll: comando não encontrado
codebehind1.dll: commande introuvable
codebehind1.dll: command not found
codebehind1.dll: käsku ei ole
codebehind1.dll: không tìm thấy lệnh
codebehind1.dll: komanda nerasta
codebehind1.dll: Kommando nicht gefunden.
codebehind1.dll: kommandot finns inte
codebehind1.dll: komut yok
codebehind1.dll: nie znaleziono polecenia
codebehind1.dll: níor aimsíodh an t-ordú
codebehind1.dll: no se encontró la orden
codebehind1.dll: no s'ha trobat l'ordre
codebehind1.dll: opdracht niet gevonden
codebehind1.dll: parancs nem található
codebehind1.dll: perintah tidak ditemukan
codebehind1.dll: príkaz nenájdený
codebehind1.dll: příkaz nenalezen
codebehind1.dll: команда не найдена
codebehind1.dll: командата не е открита
codebehind1.dll: 命令找不到
codebehind1.dll: コマンドが見つかりません