Cannot change the power source to battery

Hy!

I have problem with my battery.I cant use it without cable,because it shut down when i take out the cable. When i click the battery icon it says "the battery is not charging" and i cant change in the energy saver preferences from power adapter( 'Settings for: Power adapter') to battery. I installed Battery Update 1.4 but it still isnt working.
Any idea,how can i fix it?
The battery was good for 2 years, but now it went wrong.

Sorry for my bad english.

What Mac do you have?

Model Name: MacBook
Model Identifier: MacBook4,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2.4 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 3 MB
Memory: 4 GB
Bus Speed: 800 MHz