cups-genppd.5.2: 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

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/sbin/cups-genppd.5.2 - from package: gutenprint-cups

You may install the required package with command yum install {package}
Error in other languages:
cups-genppd.5.2: bevel nie gevind nie
cups-genppd.5.2: comandă negăsită
cups-genppd.5.2: comando não encontrado
cups-genppd.5.2: commande introuvable
cups-genppd.5.2: command not found
cups-genppd.5.2: käsku ei ole
cups-genppd.5.2: không tìm thấy lệnh
cups-genppd.5.2: komanda nerasta
cups-genppd.5.2: Kommando nicht gefunden.
cups-genppd.5.2: kommandot finns inte
cups-genppd.5.2: komut yok
cups-genppd.5.2: nie znaleziono polecenia
cups-genppd.5.2: níor aimsíodh an t-ordú
cups-genppd.5.2: no se encontró la orden
cups-genppd.5.2: no s'ha trobat l'ordre
cups-genppd.5.2: opdracht niet gevonden
cups-genppd.5.2: parancs nem található
cups-genppd.5.2: perintah tidak ditemukan
cups-genppd.5.2: príkaz nenájdený
cups-genppd.5.2: příkaz nenalezen
cups-genppd.5.2: команда не найдена
cups-genppd.5.2: командата не е открита
cups-genppd.5.2: 命令找不到
cups-genppd.5.2: コマンドが見つかりません