psset: 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/psset - from package: a2ps

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

On Debian possible default full paths are:

/usr/bin/psset - from package: a2ps

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