in.authd: 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 CentOS possible default full paths are:

/usr/sbin/in.authd - from package: authd

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

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