gfsview3D: 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/gfsview3D - from package: gfsview

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

Error in other languages:
gfsview3D: bevel nie gevind nie
gfsview3D: comandă negăsită
gfsview3D: comando não encontrado
gfsview3D: commande introuvable
gfsview3D: command not found
gfsview3D: käsku ei ole
gfsview3D: không tìm thấy lệnh
gfsview3D: komanda nerasta
gfsview3D: Kommando nicht gefunden.
gfsview3D: kommandot finns inte
gfsview3D: komut yok
gfsview3D: nie znaleziono polecenia
gfsview3D: níor aimsíodh an t-ordú
gfsview3D: no se encontró la orden
gfsview3D: no s'ha trobat l'ordre
gfsview3D: opdracht niet gevonden
gfsview3D: parancs nem található
gfsview3D: perintah tidak ditemukan
gfsview3D: príkaz nenájdený
gfsview3D: příkaz nenalezen
gfsview3D: команда не найдена
gfsview3D: командата не е открита
gfsview3D: 命令找不到
gfsview3D: コマンドが見つかりません