pktsetup: 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 CentOS possible default full paths are:

/usr/bin/pktsetup - from package: udftools

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

On Debian possible default full paths are:

/usr/bin/pktsetup - from package: udftools

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

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