mimeencode: 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/mimeencode - from package: perl-MIME-tools

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

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