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One of the problems faced by owners of iPhone and iPad when using or setting up Touch ID — the message «Failed. Can’t finish setting up Touch ID. Go back and retry, or Failed. Unable to complete Touch ID setup».
Usually the problem disappears itself after the next iOS upgrade, but generally wait nobody wants, and therefore see, what to do if I am unable to finish setting up Touch ID on your iPhone or iPad and how to fix the problem.
Re-creating Touch ID
This method works more often in case TouchID stopped working after iOS upgrade and does not work in any application.
Steps to rectify problem are as follows:
After that everything should work fine, and the error stating that you cannot finish setting up Touch ID will appear again.
Other ways to fix the error «unable to complete Touch ID setup»
If the method described above did not help you, it remains to try other options, which, however, are usually less effective:
And finally, if none of this helps, you should either wait for the next update of iOS or if iPhone is still under warranty, contact an official Apple service.
Note: according to reviews, many iPhone owners, faced with the problem of «unable to complete Touch ID setup», the official support says that this is a hardware issue and either change the Home button (or screen + Home button) or the entire phone.