My Toshiba satellite a300 laptop restart when i connect the power adapter. but it will charge in off mode. I can't work with connect the power adapter. give me a right solution for resolve this problem.
if I take out better after connect the power adapter and switch on it will on but 2 or 3 minutes it will restart
Ahh, too bad. It means, it's not the battery's fault. And it can't be the charger either, I guess, because it works when the computer is off... I'm afraid, you'll need to see the doctor with it, just as alyoshka suggested.
You don't have a friend around with an exactly same type of charger, do you? (Hope dies last.)
This is a known problem in some Toshiba Satellite laptops due to a faulty NEC/TOKIN Proadlizer, which requires replacement. This shows a way to repair it: http://gs138.photobucket.com/groups/q251/S1BXDWUERU/