memdiskfind: 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/bin/memdiskfind - from package: syslinux

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

On Debian possible default full paths are:

/usr/bin/memdiskfind - from package: syslinux-utils

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

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