I´ve got this super anoying problem...
Problem description:
When I connect a 3-part mouse everything works just fine but the back/forward on the mouse.
The back/forward assignment on the side buttons work just once each startup.
The second time I press back/forward I can se in the task manager and on the HD LED that the PC starts to do some work for a second or two each click.
If I assign the sidebuttons to say scroll up/down they work 100%.
History:
It´s a brand new VGN-FW31J running Vista.
The first thing I connected to the VAIO was the mouse, no other applications installed, nothing. I first thought it was my new blutooth Trust mouse wich had bad drivers or something but after updating all kind of drivers and talking to the trust support they said that i should return the mouse, probably malfunctioning. Anyhow, I restored c: and tried again before returning the mouse, same prob.
At the store I changed to a Logitech MX 620 (USB) instead and updating to the latest drivers but the problem remains! I´ve now tried to uninstall all bloatware, turing off wireless, uninstalling the mousepad, googleng for hours, talking to support people, restoring c: (again) but nooooo.
Please please please. If you have the answer or maby just an Idea! 
PS. The Loogitech works fine on my stationary computer.
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