How to Restore an iPhone to Its Previous Firmware

Restoring your iPhone to its previous software is an effective way to fix bugs, undo any damage caused by downloading faulty or unauthorized software, or simply return to an operating software you prefer. If you don't have the file for the desired firmware already on your computer, a number of websites have various iPhone firmware versions available to download. But be careful when using third-party websites and make sure you have active anti-spyware software installed on your computer.

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You can restore an iPhone to its previous firmware using your computer.

Step

Make sure you have the firmware for restoring the phone on your computer. On a Mac and PC, you will find the software in the iTunes library under "Phone Software Updates." If you need to download it, many third-party websites offer a variety of firmware downloads.

Step

Plug your iPhone into your computer and open iTunes. Wait for the software to recognize your phone.

Step

Click on your iPhone in the left-hand toolbar in iTunes. Click "Summary" in the main screen and find the restore button—but don't click it yet.

Step

Hold down the "Option" button and click "Restore" if you are using a Mac. On a PC, hold down "Shift" and click "Restore." The folder that contains the firmware updates for your phone will open on the screen.

Step

Browse the firmware folder to find the right version you want to restore. Select the file and click "Restore." The update might take a few minutes so do not disconnect your iPhone until you have received confirmation the synching is completed.

Step

Ignore any error messages that pop up, including those with the codes 1011, 1013 or 1015. Your iPhone should have been restored to its previous firmware and, once safely disconnected, is ready to use.