i recently bought a new battery charger for my dell laptop. it worked fine for a week or 2 but now it wont charge my laptop when i plug it in. i've found that the charger when plugged into the wall outlet isn't turning on because the little green light that is usually lit on the box of the charger isn't lit. so after finding this out i tried using someone else's charger and it worked for a day and the next day the same problem happened. what's going on? i hope it has doesn't have something to do with my laptop itself. please help!!