You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Level 1

4 points

Unexpected shutdown of iphone

After putting in recovery mode and then restring, I get: "The iPhone “iPhone” could not be restored. An unknown error occurred (21)."

Posted on Jan 9, 2022 8:29 PM

Top-ranking reply

Level 6

17,690 points

Posted on Jan 9, 2022 9:09 PM

Could be a hardware malfunction.

iOS update and restore errors - Apple Support

If you see one of the errors below, you might have a hardware issue:

1, 3, 11, 12, 13, 16

20, 21, 23, 26, 27, 28, 29, 34, 35, 36, 37, 40, 56

1002, 1004, 1011, 1012, 1014, 1667, 1669

View in context

Similar questions