openpgp2pem: 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/openpgp2pem - from package: monkeysphere

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

On Debian possible default full paths are:

/usr/bin/openpgp2pem - from package: monkeysphere

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

Error in other languages:
openpgp2pem: bevel nie gevind nie
openpgp2pem: comandă negăsită
openpgp2pem: comando não encontrado
openpgp2pem: commande introuvable
openpgp2pem: command not found
openpgp2pem: käsku ei ole
openpgp2pem: không tìm thấy lệnh
openpgp2pem: komanda nerasta
openpgp2pem: Kommando nicht gefunden.
openpgp2pem: kommandot finns inte
openpgp2pem: komut yok
openpgp2pem: nie znaleziono polecenia
openpgp2pem: níor aimsíodh an t-ordú
openpgp2pem: no se encontró la orden
openpgp2pem: no s'ha trobat l'ordre
openpgp2pem: opdracht niet gevonden
openpgp2pem: parancs nem található
openpgp2pem: perintah tidak ditemukan
openpgp2pem: príkaz nenájdený
openpgp2pem: příkaz nenalezen
openpgp2pem: команда не найдена
openpgp2pem: командата не е открита
openpgp2pem: 命令找不到
openpgp2pem: コマンドが見つかりません