mairix: 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/mairix - from package: mairix

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