"Thanks! But no go! It looked promising. iTunes said it was installing the iOS. But when it finished, it went back to the loop. iPhone: 'Try connecting your iPhone to a Mac ... with iTunes to activate it.' iTunes: 'The iPhone could not be activated because the activation information could not be obtained from the device.'"
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You are welcome.
Troubleshooting the Passcode...
You are welcome. So, if your iPhone is not in a boot loop, then it is the log in that is. Being locked out, you need to take this up with Apple.
Hold It Right There!:
Enter the passcode incorrectly too many times, and you'd likely be locked out for good. So, hold it right there, and refer to this link: If you Forgot the Passcode on your iPad, or your iPad is Disabled - Apple Support. It would be the one you've always entered. If you do not know it, then look for it in a location you may have stored it in.
If locked out...
Have any Proof of Purchase?
Unless you have the original packaging and receipt, you may be out of luck. If you do have it, however, then take this to an Apple Store, or an AASP (Apple Authorized Service Provider)! and they may be able to restore it. The reason for this blockage is all about Security & Privacy.