I have an old iPad 2 (2,1) with iOS 4.3.5 which won't upgrade.
It will go through the motions but then fail with an error 9 or an error 3014 if trying to update to 9.2.
Any other manually downloaded iOS's fail with a error "device isn't eligible".
Also tried older versions if iTunes with no joy.
Most of the time the iPad will go into the endless recovery loop, but I found a 3rd party tool to get it out of that and come back to a basic iPad with iOS4.
Can anyone help we get this iPad updated to something newer?