instal the last version for ios Fort Firewall 3.9.

Many iOS system repair tools or iPhone unlock software provide the service to install an IPSW file downloaded to your PC. How to Install IPSW on iPhone without iTunes - iOS 15 Supported You'll need to set up your iPhone again after restoring iPhone. Restore iPhone: This option will erase all data including apps on your iPhone and install the latest iOS on your iPhone, with the default Apple apps. This process will not restore your firmware. If you have encrypted your backup, your login info will also be restored. Once you apply the 'Restore Backup' option to your iOS device, your contacts, calendars, notes, text messages, and settings will be restored. Restore Backup: This option is available when you have previously backed up your data on iOS devices to iTunes. What is the Difference Between Restore Backup and Restore iPhone in iTunes? With an IPSW file, you can upgrade or downgrade your iOS system manually without iTunes. IPSW file is the Apple Device Software Update File, with an extension '.ipsw.' An IPSW file contains data used by Apple to conduct system restore and update to iOS, iPadOS, tvOS, and HomePod firmware. In this article, I will share how to install an IPSW file on iPhone without/with iTunes. Many third-party tools can help you install an IPSW file to avoid some unexpected installation failures. In this case, you need to manually install an IPSW file to restore your iPhone system to a previous version.

If you have accidentally upgraded your iOS system to the latest version and want to roll back, there is no way to do this via neither the 'Restore Backup' nor the 'Restore iPhone' option in iTunes.

Instal the last version for ios Fort Firewall 3.9.