pgpewrap: 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/pgpewrap - from package: mutt

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