gmimeuudecode: 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/gmimeuudecode - from package: gmime

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

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