Q: My battery is not charging at all.

I would try a PMU reset first then lookup the battery condition with the Apple menu/About This Mac/more info or System Information.app found in the Utilities folder. The battery info is found under System Information.app/System Report/Hardware/Power

http://support.apple.com/kb/HT1431

Check Battery indicates your battery may be dying or defective. Is it removable and has it been calibrated?

Some more discussions on checking batteries.

http://www.macyourself.com/2011/01/23/check-your-macs-battery-health-to-see-if-i t-needs-to-be-replaced/

http://support.apple.com/kb/ht1519

http://support.apple.com/kb/HT1490

Links to information on how and why to calibrate.

http://support.apple.com/kb/ht1490

http://www.maclife.com/article/howtos/how_maintain_your_macbook_battery

http://www.tuaw.com/2012/08/20/mac-101-battery-not-charging-recalibration-may-be -the-answer/

Is this an iBook or MacBook?

This would indicate these possible problems;

The battery is defective

There could be a problem with the DC-Inboard

The power Supply is faulty or defective.

Have you tried another power supply?

How old is the battery?

In order for you to check your power adapter, you need another one. The problem could be with a defective power supply.With a fault like this, you need to eliminate anything paternally causing the problem. A problem like this has often be due to defective power adapters and defective batteries.

Sorry to weigh in so late!

A battery that old is almost certainly on its last legs and should be replaced anyway. But if you need to eke out a little more life from it (replacement batteries aren't cheap), then definitely follow Knucklesmac's advice: borrow another power adapter and try charging your battery. If the battery still won't charge, you'll need to replace it now.

And if it does charge, start saving up for its replacement... because a four-and-a-half-year-old battery is going to let you down very soon.

I had been suffering from this very thing for a few months.  Out of desperation today, I tried something rather unorthodox... and it ~worked~.

I momentarily placed a piece of aluminum foil between the MagSafe connecter and the socket.

After letting it snap, crackle, and pop for a very quick second, I removed the foil and reinserted the MagSafe connecter into the socket as usual.

...and it started charging immediately.

...and has held this connection all day.

In response to WhBower: Holy crap, that worked. What in the ****? You just saved me a huge headache sir (or madam). Thanks!

My pleasure, M.

You might need to do it again in about a month, which is what happened with me.

Other than that, though, it seems to still be working just fine.

Here's to aluminum foil!

Sir WHBower