I picked up a Macbook pro a while ago with a cracked screen. After installing a new one (screen) I then noticed the battery emblem has a black x in it. The computer says that there isn't one installed yet there is. Battery coconut doesn't see it either. When the mag charger is plugged in it stays green, never turn orange or goes dim, stays a nice bright green. Now for the fun part. If I install a charged batty everything stays the same yet if I pull the plug the battery takes over and everything runs fine with the exception of the black x. The computer will not boot up from the battery, got to have the charger on it but as soon as it is up and running I can pull the charger and it will run till the battery is depleted I then change it out for another charged battery and keep on going. Any ideas?