pushpin-proxy: 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/pushpin-proxy - from package: pushpin

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

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