ngircd: 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 CentOS possible default full paths are:

/usr/sbin/ngircd - from package: ngircd

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/sbin/ngircd - from package: ngircd

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