I had same issue with my iPad2 with iOS 9.3.5 on 10/06/2017 around about 10:35 p.m.
I turned off iPad2, then launched iTunes (latest version), and then plug iPad2 up to usb port of laptop to allow laptop to power up iPad2. Then after a minute or so received a message asking to allow iTunes to access your device (iPad2). I allowed, and then receive message to check my device, which then prompted for apple id and password. After entering credentials iTunes gave me a similar message, but my iPad 2 did activate and my home screen with all my icons, apps...etc loaded like it normally does.
So, are you plugging up the iPad2 turned on or off before launching iTunes. I would suggest to turn iPad2 off, then launch iTunes (make sure latest version), and then plug iPad2 up to Laptop or PC to allow that device to power up iPad2. iTunes should pick up on the iPad2 as I mentioned above.
I hope this helps.