zcmp: 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 CentOS possible default full paths are:

/usr/bin/zcmp - from package: gzip

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/bin/zcmp - from package: gzip
/bin/zcmp - from package: zutils

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