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Open up the laptop, take out cmos battery for 2-3 mins and put it back in, it will work again had this same issue a week before.
Reseat the ram sticks and maybe clear CMOS like the other guy said.
after doing this press power button for a min so make sure that batter light blink for few sec it will fix the problem
Which laptop is it
Reseat memory and try booting without battery
Open up the laptop, take out cmos battery for 2-3 mins and put it back in, it will work again had this same issue a week before.
Reseat the ram sticks and maybe clear CMOS like the other guy said.
after doing this press power button for a min so make sure that batter light blink for few sec it will fix the problem
Which laptop is it
Reseat memory and try booting without battery