exicyclog: 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/exicyclog - from package: exim

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

On Debian possible default full paths are:

/usr/sbin/exicyclog - from package: exim4-base

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

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