What can you do when your laptop battery won't charge

If you discount the battery, your laptop could probably live pretty much forever. Sure, a 10 year old laptop isn't much fun to use -- its 5-generation-old technology is as slow as frozen molasses -- but if it won't spring for a new one, you can at least trust that it'll keep working without major headaches.
Except for the battery.
Laptop batteries tend to live for about 3 years with routine use. After a few years, you might find that your laptop only runs for 15 or 20 minutes on a charge, When you can't get through a full meeting without plugging in your laptop, it's time to buy a laptop replacement battery. But if your battery isn't charging properly and you haven't been using it for the better part of a presidential term of office, you might want to try a little troubleshooting first to see if the problem doesn't lie elsewhere.
Here are some things to check:
Try charging the laptop with the power off. Some laptops draw a lot of power -- so much so that they can't efficiently charge the battery and run demanding tasks at the same time. If the battery doesn't seem to be getting fully charged, shut down the laptop entirely and see how it goes.
Make sure that the AC adapter is working. The problem might also lie in the power adapter. This one is easy to test: Remove the battery completely from the laptop and try running the laptop using the AC adapter. If you can use the computer for a couple of hours without problems, the adapter is obviously okay.
Clean the battery contacts. Since you removed the battery anyway, make sure that the contacts on the battery and the laptop are clean. Replace the battery and try charging it again.
Try a deep charge. If the battery is in a bad state, you might be able to bring it back to life with a deep charge cycle. First, make sure it's complete discharged by running the laptop with the battery installed (and the AC adapter removed) until the laptop completely dies. Then charge the laptop overnight.
If you try all of these troubleshooting steps and your battery is still not working properly, it's time to get a new battery. Or, if the laptop suffers an unfortunate accident, it might be time to replace the whole thing.