pfsglview: 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 Debian possible default full paths are:

/usr/bin/pfsglview - from package: pfsglview

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

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