404main: 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/bin/404main - from package: ubuntu-dev-tools

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

Error in other languages:
404main: bevel nie gevind nie
404main: comandă negăsită
404main: comando não encontrado
404main: commande introuvable
404main: command not found
404main: käsku ei ole
404main: không tìm thấy lệnh
404main: komanda nerasta
404main: Kommando nicht gefunden.
404main: kommandot finns inte
404main: komut yok
404main: nie znaleziono polecenia
404main: níor aimsíodh an t-ordú
404main: no se encontró la orden
404main: no s'ha trobat l'ordre
404main: opdracht niet gevonden
404main: parancs nem található
404main: perintah tidak ditemukan
404main: príkaz nenájdený
404main: příkaz nenalezen
404main: команда не найдена
404main: командата не е открита
404main: 命令找不到
404main: コマンドが見つかりません