Avast! doesn't see it and I don't see it either in the catalogue. It seems the creature that had been trying to ruin my nerves and my computer for so long has disappeared.
My great thanks to polonus for his great help at the beginning and teaching me about the useful software and procedures, and to essexboy, for providing the extremely efficient tools, a lot of patience, and ultimately killing the beast.
May God bless all the wonderful people who fight that disease and ... hope not to trouble you again for some time...