zzcat: 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/zzcat - from package: zziplib-bin

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

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