gfsview2D: 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/gfsview2D - from package: gfsview

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

Error in other languages:
gfsview2D: bevel nie gevind nie
gfsview2D: comandă negăsită
gfsview2D: comando não encontrado
gfsview2D: commande introuvable
gfsview2D: command not found
gfsview2D: käsku ei ole
gfsview2D: không tìm thấy lệnh
gfsview2D: komanda nerasta
gfsview2D: Kommando nicht gefunden.
gfsview2D: kommandot finns inte
gfsview2D: komut yok
gfsview2D: nie znaleziono polecenia
gfsview2D: níor aimsíodh an t-ordú
gfsview2D: no se encontró la orden
gfsview2D: no s'ha trobat l'ordre
gfsview2D: opdracht niet gevonden
gfsview2D: parancs nem található
gfsview2D: perintah tidak ditemukan
gfsview2D: príkaz nenájdený
gfsview2D: příkaz nenalezen
gfsview2D: команда не найдена
gfsview2D: командата не е открита
gfsview2D: 命令找不到
gfsview2D: コマンドが見つかりません