Want to upgrade my Ipad2 to IOS 6 - Apple iPad 32 GB 3G Tablet PC

That iPad2 cannot be upgraded to IOS 10.

https://discussions.apple.com/thread/8065208

It might be a bug - so ask Apple. ..... But first you might like to check if you are running of of memory space use Settings > General > Usage. The iPad will fill up - especially with mail & photos (mine has).

You cannot. The first generation ipad cannot be upgraded past IOS5. You will need new hardware to take advantage of the newer IOS6.

If you have a first gen. iPad you cannot update as it is not compatible with iOS 6

Here Are All The iOS 6 Direct Download Links For Each Supported iDevice...

the first gen. iPad is not compatible with iOS 6
- you need a newer one....
Apple iOS 6 Finally Available for Download Direct Download Link Download Apple iOS 6

if you have a first gen. iPad you cannot update to iOS 6 as it is only compatible to iPad2 and newer:
First gen iPad not getting iOS 6 update Apple confirms

- meanwhile you may download the iOS 8.1.2 which is good and some Apps require it....
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There are two ways to upgrade the iOS version of your iPad
- via connecting the device to iTunes on a computer
- or directly from within the device, but only since iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update)
just go to: settings - general - software update

First Generation iPads can use iOS 5
- but iOS 6 / 7 / 8 need an iPad 2 or newer and are not compatibel with first gen. iPhone
-updates can be made in iTunes connected to a computer or under settings - general - software update
Upgrade iOS from within iOS device
(valid for iOS 5 and above)
Since iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update). To upgrade to iOS 6/7/8, simply navigate to Settings > General > Software Update. The screenshot below demonstrates how to do so on an iPad, but this is also valid for the iPhone and iPod Touch.

in iTunes:
How to update to iOS 7

Plug your iPad 2 into the device where you run iTunes. In iTunes, select the iPad in the left column, then select the Summary panel. At the upper right, continue by downloading and installing the latest version of iOS that will run on that device. We use iOS 7 on our iPad 2 - and it runs very nicely.

How to do I update to iOS 5?
There are two ways to upgrade the iOS version of your iPad
- via connecting the device to iTunes on a computer
- or directly from within the device, but only since iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update)
just go to: settings - general - software update