vtkHashSource-6.1: command not found

Have You tried accessing the binary with the full path?

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/vtkHashSource-6.1 - from package: vtk6

You may install the required package with command apt-get install {package}
Error in other languages:
vtkHashSource-6.1: bevel nie gevind nie
vtkHashSource-6.1: comandă negăsită
vtkHashSource-6.1: comando não encontrado
vtkHashSource-6.1: commande introuvable
vtkHashSource-6.1: command not found
vtkHashSource-6.1: käsku ei ole
vtkHashSource-6.1: không tìm thấy lệnh
vtkHashSource-6.1: komanda nerasta
vtkHashSource-6.1: Kommando nicht gefunden.
vtkHashSource-6.1: kommandot finns inte
vtkHashSource-6.1: komut yok
vtkHashSource-6.1: nie znaleziono polecenia
vtkHashSource-6.1: níor aimsíodh an t-ordú
vtkHashSource-6.1: no se encontró la orden
vtkHashSource-6.1: no s'ha trobat l'ordre
vtkHashSource-6.1: opdracht niet gevonden
vtkHashSource-6.1: parancs nem található
vtkHashSource-6.1: perintah tidak ditemukan
vtkHashSource-6.1: príkaz nenájdený
vtkHashSource-6.1: příkaz nenalezen
vtkHashSource-6.1: команда не найдена
vtkHashSource-6.1: командата не е открита
vtkHashSource-6.1: 命令找不到
vtkHashSource-6.1: コマンドが見つかりません