I'd email you but am afraid your problem will find its way back down the wires and get me.

I've seen this before. It's not a person hacking you, it's a superintelligent computer program which has been sent back in time from the future to thwart you from doing something that threatens it's existence.

It is currently living in thousands of zombie machines around the planet and every time youswitch off, it waits patiently for you to reappear somewhere and then reinfects your system with its cadre of DDOS attacks and worms.

What you need to do is track down the guy who created the program in the first place and, ahem, "convince him not to do so, somehow". his name is Bill Gates.

Having done that, you'll then need to lure the current program into some sort of steel smelting plant and fight it until it falls into a vat of molten steel and thrashes around until it's dead.

The future of the world is in your hands, OP. God Speed.