makemap: 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/makemap - from package: opensmtpd
/usr/sbin/makemap - from package: sendmail
/usr/bin/makemap - from package: sendmail

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

On Debian possible default full paths are:

/usr/sbin/makemap - from package: sendmail-bin

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

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