1. If you have a Mac running macOS Mojave 10.14 or a PC, connect your iPhone to your computer and launch iTunes. If you have a Mac running macOS Catalina 10.15 or later, open Finder. It makes no difference whether your iPhone is turned on or off.
2. For 8 seconds, press and hold the Sleep/Wake and Home buttons (iPhone 6s and below) or the volume down button (iPhone 7) simultaneously.
3. Release the Sleep/Wake Button after 8 seconds, but keep holding the Home Button (for iPhone 6s and lower) or the volume down button (for iPhone 7) until your iPhone shows in iTunes or Finder.
4. An iPhone in recovery mode has been recognized by iTunes.
5. Let go of the Home Button or volume down button. Your iPhone’s display will be completely black if you’ve successfully entered DFU mode. If it’s not, try again from the beginning.
6. Restore your iPhone using iTunes or Finder.

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