pyplusplus_gui: 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 Debian possible default full paths are:

/usr/bin/pyplusplus_gui - from package: python-py++

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

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