Unable to install iOS 9.3
message is - no longer connected to the Internet. All internet connections OK except update.
iPad Air, iOS 9.3
Apple has pulled the iOS 9.3 update for older devices (iPad Airs and previous, iPhone 5s and previous) due to problems with Activation. See these articles for details and possible workarounds.
http://www.imore.com/apple-working-ios-93-fix-older-iphone-ipad
https://support.apple.com/en-us/HT206203
A new build for the iPad 2 is now available that does not require the Activation step. A new build for the other devices is not yet available.