html2po: 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/html2po - from package: translate-toolkit

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

On Debian possible default full paths are:

/usr/bin/html2po - from package: translate-toolkit

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

Error in other languages:
html2po: bevel nie gevind nie
html2po: comandă negăsită
html2po: comando não encontrado
html2po: commande introuvable
html2po: command not found
html2po: käsku ei ole
html2po: không tìm thấy lệnh
html2po: komanda nerasta
html2po: Kommando nicht gefunden.
html2po: kommandot finns inte
html2po: komut yok
html2po: nie znaleziono polecenia
html2po: níor aimsíodh an t-ordú
html2po: no se encontró la orden
html2po: no s'ha trobat l'ordre
html2po: opdracht niet gevonden
html2po: parancs nem található
html2po: perintah tidak ditemukan
html2po: príkaz nenájdený
html2po: příkaz nenalezen
html2po: команда не найдена
html2po: командата не е открита
html2po: 命令找不到
html2po: コマンドが見つかりません