Compaq Presario Charging

A compaq presario 710us was only working with the ac. the battery seemed
dead and would not charge. we purchased a brand new battery and it will not
work. when the ac is plugged in the battery charge light blinks for a
moment and the goes staedy orange. The laptop will boot up and run fine on
ac. The battery management software sees that a battery is in place and
says it is charging but it never goes above 0% charge. We did try changing
out the battery charger circuit board with no improvement. any ideas