makebootfat: 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 CentOS possible default full paths are:

/usr/bin/makebootfat - from package: makebootfat

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

On Debian possible default full paths are:

/usr/bin/makebootfat - from package: makebootfat

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