Try this First...
Turn the iPad Off... ( if it isn’t already )
Press and Hold the Sleep/Wake Button and the Home Button at the Same Time...
Wait for the Apple logo to Appear and then Disappear...
Usually takes about 15 - 20 Seconds... ( But can take Longer...)
Release the Buttons...
Turn the iPad On...
"The fastest way to charge your iPad is with the included 10W USB Power Adapter.
iPad will also charge, although more slowly, when attached to a computer with a high-power USB port (many recent Mac computers) or with an iPhone Power Adapter.
When attached to a computer via a standard USB port (most PCs or older Mac computers) iPad will charge, but only when it's in sleep mode.
Make sure your computer is on while charging iPad via USB. If iPad is connected to a computer that’s turned off or is in sleep or standby mode, the iPad battery will continue to drain."
If no joy... Take iPad... the iPad Charger and its Cable to an Apple Store or AASP and have them Checked...
Be sure to make an appointment first.
The quickest way (and really the only way) to charge your iPad is with the included 10W USB Power Adapter. iPad will also charge, although more slowly, when attached to a computer with a high-power USB port (many recent Mac computers) or with an iPhone Power Adapter (5W). When attached to a computer via a standard USB port (most PCs or older Mac computers) iPad will charge very slowly (but iPad indicates not charging). Make sure your computer is on while charging iPad via USB. If iPad is connected to a computer that’s turned off or is in sleep or standby mode, the iPad battery will continue to drain.
Apple recommends that once a month you let the iPad fully discharge & then recharge to 100%.
How to Calibrate Your Mac, iPhone, or iPad Battery
At this link http://www.tomshardware.com/reviews/galaxy-tab-android-tablet,3014-11.html , tests show that the iPad 2 battery (25 watt-hours) will charge to 90% in 3 hours 1 minute. It will charge to 100% in 4 hours 2 minutes. The new iPad has a larger capacity battery (42 watt-hours), so using the 10W charger will obviously take longer. If you are using your iPad while charging, it will take even longer. It's best to turn your new iPad OFF and charge over night. Also look at The iPad's charging challenge explained http://www.macworld.com/article/1150356/ipadcharging.html
Also, if you have a 3rd generation iPad, look at
Apple: iPad Battery Nothing to Get Charged Up About
Apple Explains New iPad's Continued Charging Beyond 100% Battery Level
New iPad Takes Much Longer to Charge Than iPad 2
Apple Batteries - iPad http://www.apple.com/batteries/ipad.html
Extend iPad Battery Life (Look at pjl123 comment)
New iPad Slow to Recharge, Barely Charges During Use
Tips About Charging for New iPad 3
Prolong battery lifespan for iPad / iPad 2 / iPad 3: charging tips
iPhone, iPod, Using the iPad Charger
Install and use Battery Doctor HD
In rare instances when using the Camera Connection Kit, you may notice that iPad does not charge after using the Camera Connection Kit. Disconnecting and reconnecting the iPad from the charger will resolve this issue.
I have this same issue, ever since I updated to os6 it won't charge in the wall or on the computer.. I have to plug it in and unplug it then plug it in about 20 times befor it"catches" I've reset it completely. erased it and reset it.. did not help. Can we uninstall the update????? this is really fustrating and APPLE isn't being helpful because I'm not under warenty but if it's an os issue shouldn't they be supportive?? I'm really upset by this!
So, today I was able to connect my ipad to the computer and completely restore to factory settings, first I backed it up to icloud, then through itunes I was able to erase my ipad2 completely then disconnect from the computer and through icloud, restore my system. It worked... the first time I restored my ipad I didn't do it through itunes so the system didn't get erased, so you have to go through itunes.
back up your ipad on icloud first...
connect ipad.. do not sync.
click on ipad icon in your itunes program.
go to summary
once restored disconnect and get your back up from icloud,.
worked for me!!
All you need to do is use the wall charger if you are not satisfied with it saying not charging. Other wise even when it's plugged in to the computer and it says not charging it is charging but very slowly like"Texas Mac man" said. K?
The battery in the iPad is much larger than the ones in the iPod and iPhone. They have different circuitry and require a 10 wat charger not the 5 or less watts that a standard USB port on most laptops provide. Some laptops have a high output USB port but there are so few devices that need that kind of power to charge.
This is why when you use the 5 watt iPhone/iPod wall charger it gets so hot when you use it to charge an iPad.