Hi Shane
Thank you for the reply. I went to msconfig, to Selective Startup, deactivated all services, reactivated all again, one by one, and no more message box shows up. In the Startup column I just activated the items that I felt I was needing. I don't know which programs were activated before, so it seems I must try all, one at a time to find out which was causing that trouble.
Now I have a new problem, the up-down function of my touchpad (in the right side of the touchpad) does not work, although I have activated the program (Synaptics) to start up. And it happens too that the Synaptics item is missing from the down right bar.
Please give me one more hint.