Use the steps in this article if your device disconnects during syncing or you see one of these alert messages: If one of these steps resolves the issue, but it comes back later, make sure you haven't changed how the device is connected.For example, check to see if you plugged the device into a specific accessory, or used a specific cable that reintroduced the issue. (Put your i Phone in DFU Mode by to do so, Connect your device to your computer → Force restart your i Phone by holding on sleep/wake button at once for about ten seconds → The recovery mode screen will appear on your device → If you see the option to Restore or Update, select Update.)Step #1.Waited with baited breath, finally Apple i OS 10 update was released with the great improvements in Notification Center, Quick Type, Design, etc.You can either click "Enter Recovery Mode", "Exit Recovery Mode" or use both according to the detecting result to reboot your i Phone.
Some users who restore the effected i Phone or i Pad through i Tunes discover the device is being downgraded to i OS 9.3.5, rather than updating to i OS 10.
Update: Apple has apparently fixed the problem with the OTA update.
If your device is still stuck on the i Tunes logo screen, proceed with the restore or update process with i Tunes as recommended.
Now, in the Finders menu bar, you need to select Go → Go To Folder. Up next in the box, you will have to type the following location and press Enter. The Finder window will appear and the host file will be selected. After the process is completed, you have to put the host file into the folder.
Once you have got it, then drag it to your desktop. You have to use finder to search your “hosts” file and then drag it to your desktop. Launch the i Tunes your computer and try to restore your device.