1. Download the iOS 10 IPSW that matches your device. It's available on the internet, but make sure you find files that come from Apple's servers.
2. Connect your device to iTunes. Place it in DFU mode if it isn't already showing the Connect to iTunes screen.
3. Option/Control (Mac/PC) click "Update" and find the IPSW you downloaded earlier and click Update again. If you cannot update, repeat this step and click "Restore".
If the Update option works, you won't lose any data. I wish people would research before they have a meltdown over losing their data on their devices. Also, make sure you make backups. This experience is a good reason why you should.
2. Connect your device to iTunes. Place it in DFU mode if it isn't already showing the Connect to iTunes screen.
3. Option/Control (Mac/PC) click "Update" and find the IPSW you downloaded earlier and click Update again. If you cannot update, repeat this step and click "Restore".
If the Update option works, you won't lose any data. I wish people would research before they have a meltdown over losing their data on their devices. Also, make sure you make backups. This experience is a good reason why you should.