rzip: command not found

Have You tried accessing the binary with the full path?

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/rzip - from package: rzip

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