mandrill: 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/mandrill - from package: python-mandrill

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

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