Take it back, get a Logitech Nano then a WOW pad and have done with it.
Just bought the microsoft wireless mobile mouse 3500.
-My battery is hardly lasting a day. Good stnadard duracell batteries.
-And I dont believe the mouse switches off automatically.
Same problems anyone ?
Thanks.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic