Thank you very much!Now, when trying to update it seems I should update all the packages from knoppix por something like that. Maybe this mix of versions in knoppix (stable, testing...) make things more difficult to update with some security and not breaking the o.s., but it's also what makes it so great. So, I am a bit loss about what to do...My preference would be an usb o.s. as fast as knoppix with the option to update some important programs like the browser and security problems. Now I use Firefox downloaded manually. I have tried to update chromium or install chrome without success. I love knoppix and I don't know if this is posible, even paying for it.