Chosen Solution
Tried to update phone’s OS from 8.2.3(or something) to 10.2.3 only to have it stuck with the apple logo and the progress bar. As it reaches about 70 percent of the bar, it stops moving forward and eventually restarts. I put it into DFU mode, tried updating with another computer and eventually it worked. Unfortunately, I’m now trying to revert back to the backup I had saved of the prior OS only to be stuck with the same problem with the progress bar and the apple logo as it reboots endlessly as the bar reaches about 70% and stops. Am glad to provide any other helpful info.
Are you trying to restore the whole IOS system or just your files? And you didn’t by any chance happen to save your SSH blob? Unless you have, there is no way to downgrade your phone as Apple has stopped signing older versions of IOS.
Not 100% sure this will work for you as it did me, but I heated up the phone a bit…about 80c to the back where it was very warm to touch and it completed with no errors. I eventually removed and reballed the NAND and issue went away all together.
