pswhite: 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/pswhite - from package: ncl

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

On Debian possible default full paths are:

/usr/bin/pswhite - from package: ncl-ncarg

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

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