po2prop: 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/po2prop - from package: translate-toolkit

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

On Debian possible default full paths are:

/usr/bin/po2prop - from package: translate-toolkit

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

Error in other languages:
po2prop: bevel nie gevind nie
po2prop: comandă negăsită
po2prop: comando não encontrado
po2prop: commande introuvable
po2prop: command not found
po2prop: käsku ei ole
po2prop: không tìm thấy lệnh
po2prop: komanda nerasta
po2prop: Kommando nicht gefunden.
po2prop: kommandot finns inte
po2prop: komut yok
po2prop: nie znaleziono polecenia
po2prop: níor aimsíodh an t-ordú
po2prop: no se encontró la orden
po2prop: no s'ha trobat l'ordre
po2prop: opdracht niet gevonden
po2prop: parancs nem található
po2prop: perintah tidak ditemukan
po2prop: príkaz nenájdený
po2prop: příkaz nenalezen
po2prop: команда не найдена
po2prop: командата не е открита
po2prop: 命令找不到
po2prop: コマンドが見つかりません