ziproxy: 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/ziproxy - from package: ziproxy

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

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