Is that a MacBook with an easily removable battery or did you need to remove the back? Depending on the model do this it might fix it:
Resetting the SMC & PRAM on portables with a battery you should not remove on your own1. Shut down the computer.2. Plug in the power adapter to a power source, connecting it to the Mac if its not already connected.3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.4. Release all the keys and the power button at the same time.5. Press the power button to turn on the computer.6. Press and hold the Command-Option-P-R keys before the gray screen appears.7. Hold the keys down until the computer restarts.8. Release the keys. Note: The LED on the power adapter may change states or temporarily turn off when you reset the SMC.
Resetting the SMC and PRAM memory on Mac portables with a battery you can remove1. Shut down the computer.2. Disconnect the power adapter from the computer, if it's connected.3. Remove the battery.4. Press and hold the power button for 5 seconds.5. Release the power button.6. Reconnect the battery and power adapter.7. Locate the following keys on the keyboard: Command, Option, P, and R. You will need them in step 9.8. Turn on the computer.9. Press and hold the Command-Option-P-R keys before the gray screen appears.10. Hold the keys down until the computer restarts.11. Release the keys.
Otherwise it might be the charger unplug it from the wall for a few minutes then try again.
OK does the light on the charger come on at all?
OK that usually means it is charging how long has it been doing that?
OK I would give it some time to charge (an hour or more) then try that again. If that does not work then try a different charger or a new charger. If none of that works you have a more serious problem.
Just leave it open or bookmark the page
Let me know