Update your current iOS to iOS 10.3:
- Download and install latest iTunes from here: Download iTunes
- Open iTunes and connect your supported iPhone, iPad and iPod
- Turn off “Find my iPhone” from Settings -> iCloud -> Find My iPhone.
- Now select your device from iTunes and Click on Update while pressing “Shift Key” on Windows or “Option Key” on Mac.
- iTunes will ask for iOS IPSW file, browse and select the file you downloaded. iTunes will prompt about the installation. Click yes.
- Wait for few minutes and your iOS will update to iOS 10.3
Fresh Install iOS 10.3:
- Download and install latest iTunes from here: Download iTunes
- Turn off “Find my iPhone” from Settings -> iCloud -> Find My iPhone.
- Put your device into recovery mode using this guide: How to enter recovery mode on iOS.
- Connect your device to PC or Mac and open iTunes.
- iTunes will tell you that your device is in recovery mode. Install iOS.
- Click on Restore while pressing “Shift Key” on Windows or “Option Key” on Mac.
- iTunes will ask you the iOS 10.3 file you want to install. Select the file download from the previous mention links on Page 1 of this guide.
- Now sit back and wait for iTunes to install iOS 10.3 on your supported iPhone, iPad and iPod.